{"id":200,"date":"2020-09-15T15:53:03","date_gmt":"2020-09-15T10:53:03","guid":{"rendered":"https:\/\/talib.pk\/test-preparation\/?p=200"},"modified":"2020-09-15T15:53:03","modified_gmt":"2020-09-15T10:53:03","slug":"physics-chapter-16-alternating-current-mcqs-2nd-year","status":"publish","type":"post","link":"https:\/\/talib.pk\/test-preparation\/physics-chapter-16-alternating-current-mcqs-2nd-year\/","title":{"rendered":"Physics Chapter 16 Alternating Current MCQs 2nd Year"},"content":{"rendered":"<div class=\"28d95f43054b69d67289d6316e9506d8\" data-index=\"1\" style=\"float: none; margin:12px 0 12px 0; text-align:center;\">\n<script async src=\"\/\/pagead2.googlesyndication.com\/pagead\/js\/adsbygoogle.js\"><\/script>\r\n<!-- talib-new -->\r\n<ins class=\"adsbygoogle\"\r\n     style=\"display:block\"\r\n     data-ad-client=\"ca-pub-3438155045791616\"\r\n     data-ad-slot=\"6774242552\"\r\n     data-ad-format=\"auto\"><\/ins>\r\n<script>\r\n(adsbygoogle = window.adsbygoogle || []).push({});\r\n<\/script>\n<\/div>\n<p>Here you can get the Physics Chapter 16 Alternating Current MCQs 2nd Year for the Entry Test preparations. The current which is produced by a voltage source whose polarity keeps on reversing is called Alternating Current. There are many AC circuits used to supply Alternating current. In a capacitor, direct current cannot flow. So alternating current is used in the capacitors. The study of AC in an inductor is quite important. The term impedance is used to show the combined effect of resistance and reactance. There are R-C and R-L series circuits. Electromagnetic waves require no medium for their propagation. A term called modulation is used to combine low-frequency signal with the high-frequency radio wave. So, this is a short introduction to this chapter. Have a look at the important MCQs of this chapter below.<\/p>\n<h2 style=\"text-align: center;\">Physics Chapter 16 Alternating Current MCQs 2nd Year<\/h2>\n<p><img decoding=\"async\" loading=\"lazy\" class=\"size-full wp-image-375 aligncenter\" src=\"https:\/\/talib.pk\/test-preparation\/wp-content\/uploads\/2020\/09\/Physics-2nd-Year-MCQs-9.jpg\" alt=\"Physics Chapter 16 Alternating Current MCQs 2nd Year\" width=\"300\" height=\"300\" srcset=\"https:\/\/talib.pk\/test-preparation\/wp-content\/uploads\/2020\/09\/Physics-2nd-Year-MCQs-9.jpg 300w, https:\/\/talib.pk\/test-preparation\/wp-content\/uploads\/2020\/09\/Physics-2nd-Year-MCQs-9-150x150.jpg 150w\" sizes=\"(max-width: 300px) 100vw, 300px\" \/><\/p>\n<h3><strong>KEY POINTS<\/strong><\/h3>\n<div class=\"box info  alignleft\" style=\"width:100%\"><div class=\"box-inner-block\"><i class=\"fa tie-shortcode-boxicon\"><\/i>\n\t\t\t\n<div class=\"lightbulb tie-list-shortcode\"><strong><br \/>\n<\/strong><\/p>\n<ul>\n<li>Alternating Current<\/li>\n<li>C circuits<\/li>\n<li>C through a Resistor<\/li>\n<li>C through a capacitor<\/li>\n<li>C through an inductor<\/li>\n<li>Impedance<\/li>\n<li>R-C and R-L series circuits<\/li>\n<li>Series Resonance circuit<\/li>\n<li>Parallel Resonance circuit<\/li>\n<li>Principle of Metal Detectors<\/li>\n<li>Electromagnetic waves<\/li>\n<li>Modulation<\/li>\n<\/ul>\n<\/div>\n\t\t\t<\/div><\/div>\n<p>&nbsp;<\/p>\n<p><strong><span style=\"color: #ff6600;\">Question#01<\/span>: A Choke is used as resistance in ______.<\/strong><\/p>\n<ul>\n<li>DC circuit<\/li>\n<li>AC circuit<\/li>\n<li>Both AC and DC<\/li>\n<li>Full-wave rectifier circuit<\/li>\n<\/ul>\n<div class=\"clear\"><\/div><div class=\"toggle close\"><h3 class=\"toggle-head-open\">Answer<i class=\"fa fa-angle-up\"><\/i><\/h3><h3 class=\"toggle-head-close\">Answer<i class=\"fa fa-angle-down\"><\/i><\/h3><div class=\"toggle-content\">\n\t\t\t<strong>AC circuit<\/strong>\n\t\t\t<\/div><\/div>\n<p><strong><span style=\"color: #ff6600;\">Question#02<\/span>: At resonance, the value of the power factor in an L-C-R series circuit is________.<\/strong><\/p>\n<ul>\n<li>Zero<\/li>\n<li>1\/2<\/li>\n<li>1<\/li>\n<li>non-definite<\/li>\n<\/ul>\n<div class=\"clear\"><\/div><div class=\"toggle close\"><h3 class=\"toggle-head-open\">Answer<i class=\"fa fa-angle-up\"><\/i><\/h3><h3 class=\"toggle-head-close\">Answer<i class=\"fa fa-angle-down\"><\/i><\/h3><div class=\"toggle-content\">\n\t\t\t<strong>1<\/strong>\n\t\t\t<\/div><\/div>\n<p><strong><span style=\"color: #ff6600;\">Question#03<\/span>: An AC series circuit contains 4ohm resistance and 3ohm inductive resistance. The impedance of the circuit is______.<\/strong><\/p>\n<ul>\n<li>1ohm<\/li>\n<li>5ohm<\/li>\n<li>7ohm<\/li>\n<li>7\/2 ohm<\/li>\n<\/ul>\n<div class=\"clear\"><\/div><div class=\"toggle close\"><h3 class=\"toggle-head-open\">Answer<i class=\"fa fa-angle-up\"><\/i><\/h3><h3 class=\"toggle-head-close\">Answer<i class=\"fa fa-angle-down\"><\/i><\/h3><div class=\"toggle-content\">\n\t\t\t<strong>5ohm<\/strong>\n\t\t\t<\/div><\/div>\n<p><strong><span style=\"color: #ff6600;\">Question#04<\/span>: An inductive coil has a resistance of 100ohm. When an AC signal of frequency 1000Hz is fed to the coil, the applied voltage leads the current by 45 degrees. What is the inductance of the coil?<\/strong><\/p>\n<ul>\n<li>10mH<\/li>\n<li>12mH<\/li>\n<li>16mH<\/li>\n<li>20mH<\/li>\n<\/ul>\n<div class=\"clear\"><\/div><div class=\"toggle close\"><h3 class=\"toggle-head-open\">Answer<i class=\"fa fa-angle-up\"><\/i><\/h3><h3 class=\"toggle-head-close\">Answer<i class=\"fa fa-angle-down\"><\/i><\/h3><div class=\"toggle-content\">\n\t\t\t<strong>16mH<\/strong>\n\t\t\t<\/div><\/div>\n<p><strong><span style=\"color: #ff6600;\">Question#05<\/span>: Choose the correct statement. In the case of AC circuit, ohm&#8217;s law hold for ________.<\/strong><\/p>\n<ul>\n<li>Peak values of Voltage and current<\/li>\n<li>The effective value of voltage and current<\/li>\n<li>Instantaneous values of voltage and current<\/li>\n<li>All of the above<\/li>\n<\/ul>\n<div class=\"clear\"><\/div><div class=\"toggle close\"><h3 class=\"toggle-head-open\">Answer<i class=\"fa fa-angle-up\"><\/i><\/h3><h3 class=\"toggle-head-close\">Answer<i class=\"fa fa-angle-down\"><\/i><\/h3><div class=\"toggle-content\">\n\t\t\t<strong>All of the above<\/strong>\n\t\t\t<\/div><\/div>\n<p><strong><span style=\"color: #ff6600;\">Question#06<\/span>: The phase angle between the voltage and the current in an AC circuit consisting of a resistance______.<\/strong><\/p>\n<ul>\n<li>Zero<\/li>\n<li>45degree<\/li>\n<li>90degree<\/li>\n<li>180 degree<\/li>\n<\/ul>\n<div class=\"clear\"><\/div><div class=\"toggle close\"><h3 class=\"toggle-head-open\">Answer<i class=\"fa fa-angle-up\"><\/i><\/h3><h3 class=\"toggle-head-close\">Answer<i class=\"fa fa-angle-down\"><\/i><\/h3><div class=\"toggle-content\">\n\t\t\t<strong>Zero<\/strong>\n\t\t\t<\/div><\/div>\n<p><strong><span style=\"color: #ff6600;\">Question#07<\/span>: In an LCR series circuit, if V is the effective value of the applied voltage, V<sub>R<\/sub> is the voltage across R, V<sub>L<\/sub> is the effective voltage across L and V<sub>C<\/sub> is the effective voltage across C then_________.<\/strong><\/p>\n<ul>\n<li>V=V<sub>R<\/sub> +V<sub>L<\/sub> +V<sub>C<\/sub><\/li>\n<li>V<sup>2<\/sup>=V<sub>R<\/sub><sup>2<\/sup>+V<sub>L<\/sub><sup>2<\/sup>+V<sub>C<\/sub><sup>2<\/sup><\/li>\n<li>V<sup>2<\/sup>=V<sub>R<\/sub><sup>2<\/sup>+(V<sub>L<\/sub>-V<sub>C<\/sub>)<sup>2<\/sup><\/li>\n<li>V<sup>2<\/sup>=V<sub>L<\/sub><sup>2<\/sup>+(V<sub>R<\/sub>-V<sub>C<\/sub>)<sup>2<\/sup><\/li>\n<\/ul>\n<div class=\"clear\"><\/div><div class=\"toggle close\"><h3 class=\"toggle-head-open\">Answer<i class=\"fa fa-angle-up\"><\/i><\/h3><h3 class=\"toggle-head-close\">Answer<i class=\"fa fa-angle-down\"><\/i><\/h3><div class=\"toggle-content\">\n\t\t\t<strong>V<sup>2<\/sup>=V<sub>R<\/sub><sup>2<\/sup>+(V<sub>L<\/sub>-V<sub>C<\/sub>)<sup>2<\/sup><\/strong>\n\t\t\t<\/div><\/div>\n<p><strong><span style=\"color: #ff6600;\">Question#08<\/span>: When a voltage V=V coswt is applied across a resistor of resistance R, the average power dissipated per cycle in the resistor is given by______.<\/strong><\/p>\n<ul>\n<li>V<sub>o<\/sub>\/<strong>\u221a<\/strong>2R<\/li>\n<li>V<sub>o<\/sub>\/\u221a2wR<\/li>\n<li>V<sub>o<\/sub><sup>2<\/sup>\/ 2R<\/li>\n<li>V<sub>o<\/sub><sup>2<\/sup>\/2wR<\/li>\n<\/ul>\n<div class=\"clear\"><\/div><div class=\"toggle close\"><h3 class=\"toggle-head-open\">Answer<i class=\"fa fa-angle-up\"><\/i><\/h3><h3 class=\"toggle-head-close\">Answer<i class=\"fa fa-angle-down\"><\/i><\/h3><div class=\"toggle-content\">\n\t\t\t<strong>V<sub>o<\/sub><sup>2<\/sup>\/2wR<\/strong>\n\t\t\t<\/div><\/div>\n<p><strong><span style=\"color: #ff6600;\">Question#09<\/span>: Two identical coaxial circular loops carry equal currents in the same direction. If the loops approach each other, the current in__________.<\/strong><\/p>\n<ul>\n<li>Each increase<\/li>\n<li>Each Decrease<\/li>\n<li>Each remains constant<\/li>\n<li>One increases whereas that in the other decreases<\/li>\n<\/ul>\n<div class=\"clear\"><\/div><div class=\"toggle close\"><h3 class=\"toggle-head-open\">Answer<i class=\"fa fa-angle-up\"><\/i><\/h3><h3 class=\"toggle-head-close\">Answer<i class=\"fa fa-angle-down\"><\/i><\/h3><div class=\"toggle-content\">\n\t\t\t<strong>Each increase<\/strong>\n\t\t\t<\/div><\/div>\n<p><strong><span style=\"color: #ff6600;\">Question#10<\/span>: An inductor may store energy in________.<\/strong><\/p>\n<ul>\n<li>Its electric field<\/li>\n<li>It&#8217;s coils<\/li>\n<li>Its magnetic field<\/li>\n<li>both electrical and magnetic<\/li>\n<\/ul>\n<div class=\"clear\"><\/div><div class=\"toggle close\"><h3 class=\"toggle-head-open\">Answer<i class=\"fa fa-angle-up\"><\/i><\/h3><h3 class=\"toggle-head-close\">Answer<i class=\"fa fa-angle-down\"><\/i><\/h3><div class=\"toggle-content\">\n\t\t\t<strong>Its magnetic field<\/strong>\n\t\t\t<\/div><\/div>\n<p><strong><span style=\"color: #ff6600;\">Question#11<\/span>: Average value of current and voltage over a cycle of AC is<\/strong><\/p>\n<ul>\n<li>Positive<\/li>\n<li>Negative<\/li>\n<li>both<\/li>\n<li>zero<\/li>\n<\/ul>\n<div class=\"clear\"><\/div><div class=\"toggle close\"><h3 class=\"toggle-head-open\">Answer<i class=\"fa fa-angle-up\"><\/i><\/h3><h3 class=\"toggle-head-close\">Answer<i class=\"fa fa-angle-down\"><\/i><\/h3><div class=\"toggle-content\">\n\t\t\t<strong>both<\/strong><strong>\u00a0<\/strong>\n\t\t\t<\/div><\/div>\n<p><strong><span style=\"color: #ff6600;\">Question#12<\/span>: A changing magnetic flux produces around itself an induced ________.<\/strong><\/p>\n<ul>\n<li>Magnetic field<\/li>\n<li>Electrical Field<\/li>\n<li>Electromagnetic force<\/li>\n<li>Artificial Gravitational Field<\/li>\n<\/ul>\n<div class=\"clear\"><\/div><div class=\"toggle close\"><h3 class=\"toggle-head-open\">Answer<i class=\"fa fa-angle-up\"><\/i><\/h3><h3 class=\"toggle-head-close\">Answer<i class=\"fa fa-angle-down\"><\/i><\/h3><div class=\"toggle-content\">\n\t\t\t<strong>Electrical Field <\/strong>\n\t\t\t<\/div><\/div>\n<p><strong><span style=\"color: #ff6600;\">Question#13<\/span>: Maxwell derived mathematically that the velocity of the electromagnetic waves is________.<\/strong><\/p>\n<ul>\n<li>1\/E<sub>o<\/sub><\/li>\n<li>1\/ \u221a\u00b5o\/Eo<\/li>\n<li>\u221a\u00b5o Eo<\/li>\n<li>1\/\u221a\u00b5o Eo<\/li>\n<\/ul>\n<div class=\"clear\"><\/div><div class=\"toggle close\"><h3 class=\"toggle-head-open\">Answer<i class=\"fa fa-angle-up\"><\/i><\/h3><h3 class=\"toggle-head-close\">Answer<i class=\"fa fa-angle-down\"><\/i><\/h3><div class=\"toggle-content\">\n\t\t\t<strong>1\/\u221a\u00b5o Eo<\/strong>\n\t\t\t<\/div><\/div>\n<p><strong><span style=\"color: #ff6600;\">Question#14<\/span>: Electromagnetic waves travel in the free space with the speed of______.<\/strong><\/p>\n<ul>\n<li>Gama-rays<\/li>\n<li>Positive rays<\/li>\n<li>Cathode rays<\/li>\n<li>Beta-rays<\/li>\n<\/ul>\n<div class=\"clear\"><\/div><div class=\"toggle close\"><h3 class=\"toggle-head-open\">Answer<i class=\"fa fa-angle-up\"><\/i><\/h3><h3 class=\"toggle-head-close\">Answer<i class=\"fa fa-angle-down\"><\/i><\/h3><div class=\"toggle-content\">\n\t\t\t<strong>Gama-rays<\/strong>\n\t\t\t<\/div><\/div>\n<p><strong><span style=\"color: #ff6600;\">Question#15<\/span>: The direction of propagation of an electromagnetic waves is______.<\/strong><\/p>\n<ul>\n<li>The perpendicular to the electric field<\/li>\n<li>the perpendicular to the electric and magnetic field<\/li>\n<li>perpendicular to the magnetic field<\/li>\n<li>Parallel to the electric and magnetic field<\/li>\n<\/ul>\n<div class=\"clear\"><\/div><div class=\"toggle close\"><h3 class=\"toggle-head-open\">Answer<i class=\"fa fa-angle-up\"><\/i><\/h3><h3 class=\"toggle-head-close\">Answer<i class=\"fa fa-angle-down\"><\/i><\/h3><div class=\"toggle-content\">\n\t\t\t<strong>the perpendicular to the electric and magnetic field<\/strong>\n\t\t\t<\/div><\/div>\n<p><strong><span style=\"color: #ff6600;\">Question#16<\/span>: An electromagnetic waves consists of_____.<\/strong><\/p>\n<ul>\n<li>Electric and magnetic fields moving parallel to each other<\/li>\n<li>Magnetic field moving with velocity of light in space<\/li>\n<li>Electric field moving with velocity of light<\/li>\n<li>Electric and magnetic fields moving perpendicular to each other<\/li>\n<\/ul>\n<div class=\"clear\"><\/div><div class=\"toggle close\"><h3 class=\"toggle-head-open\">Answer<i class=\"fa fa-angle-up\"><\/i><\/h3><h3 class=\"toggle-head-close\">Answer<i class=\"fa fa-angle-down\"><\/i><\/h3><div class=\"toggle-content\">\n\t\t\t<strong>Electric field moving with velocity of light<\/strong>\n\t\t\t<\/div><\/div>\n<p><strong><span style=\"color: #ff6600;\">Question#17<\/span>: Electromagnetic waves transport_______.<\/strong><\/p>\n<ul>\n<li>Energy<\/li>\n<li>Mass<\/li>\n<li>Heat<\/li>\n<li>None<\/li>\n<\/ul>\n<div class=\"clear\"><\/div><div class=\"toggle close\"><h3 class=\"toggle-head-open\">Answer<i class=\"fa fa-angle-up\"><\/i><\/h3><h3 class=\"toggle-head-close\">Answer<i class=\"fa fa-angle-down\"><\/i><\/h3><div class=\"toggle-content\">\n\t\t\t<strong>None<\/strong>\n\t\t\t<\/div><\/div>\n<p><strong><span style=\"color: #ff6600;\">Question#18<\/span>: Waves emitted from the antenna are______.<\/strong><\/p>\n<ul>\n<li>Sound waves<\/li>\n<li>Electromagnetic waves<\/li>\n<li>Radio Waves<\/li>\n<li>Modulated waves<\/li>\n<\/ul>\n<div class=\"clear\"><\/div><div class=\"toggle close\"><h3 class=\"toggle-head-open\">Answer<i class=\"fa fa-angle-up\"><\/i><\/h3><h3 class=\"toggle-head-close\">Answer<i class=\"fa fa-angle-down\"><\/i><\/h3><div class=\"toggle-content\">\n\t\t\t<strong>Electromagnetic waves<\/strong>\n\t\t\t<\/div><\/div>\n<p><strong><span style=\"color: #ff6600;\">Question#19<\/span>: A choke coil has<\/strong><\/p>\n<ul>\n<li>High Inductance and high resistance<\/li>\n<li>High inductance and low resistance<\/li>\n<li>Low inductance and high resistance<\/li>\n<li>Low inductance and high resistance<\/li>\n<\/ul>\n<div class=\"clear\"><\/div><div class=\"toggle close\"><h3 class=\"toggle-head-open\">Answer<i class=\"fa fa-angle-up\"><\/i><\/h3><h3 class=\"toggle-head-close\">Answer<i class=\"fa fa-angle-down\"><\/i><\/h3><div class=\"toggle-content\">\n\t\t\t<strong>High inductance and low resistance<\/strong>\n\t\t\t<\/div><\/div>\n<p><strong><span style=\"color: #ff6600;\">Question#20<\/span>: Natural or Resonant frequency of an LC circuit is______.<\/strong><\/p>\n<ul>\n<li>1\/4\u03c0\u00a0<strong>\u221a<\/strong>LC<\/li>\n<li>2\u03c0\u221aLC<\/li>\n<li>1\/\u221aLC<\/li>\n<li>1\/ 2\u03c0<\/li>\n<\/ul>\n<div class=\"clear\"><\/div><div class=\"toggle close\"><h3 class=\"toggle-head-open\">Answer<i class=\"fa fa-angle-up\"><\/i><\/h3><h3 class=\"toggle-head-close\">Answer<i class=\"fa fa-angle-down\"><\/i><\/h3><div class=\"toggle-content\">\n\t\t\t<strong>1\/ 2\u03c0<\/strong>\n\t\t\t<\/div><\/div>\n<p><strong><span style=\"color: #ff6600;\">Question#21<\/span>: If capacitance of L-C circuit is made four rimes then frequency of the ciircuit becomes_____.<\/strong><\/p>\n<ul>\n<li>Twice<\/li>\n<li>one half<\/li>\n<li>Four times<\/li>\n<li>None<\/li>\n<\/ul>\n<div class=\"clear\"><\/div><div class=\"toggle close\"><h3 class=\"toggle-head-open\">Answer<i class=\"fa fa-angle-up\"><\/i><\/h3><h3 class=\"toggle-head-close\">Answer<i class=\"fa fa-angle-down\"><\/i><\/h3><div class=\"toggle-content\">\n\t\t\t<strong>None<\/strong>\n\t\t\t<\/div><\/div>\n<p><strong><span style=\"color: #ff6600;\">Question#22<\/span>: A capacitance 30 micro Farad is charged by a constant current of 10mA. If initially the capacitor was uncharged, what is the time taken for the potential difference across the capacitor to reach 300V?<\/strong><\/p>\n<ul>\n<li>0.9 sec<\/li>\n<li>15 sec<\/li>\n<li>1.5 x 10^5 sec<\/li>\n<li>0.9 x 10^-2 sec<\/li>\n<\/ul>\n<div class=\"clear\"><\/div><div class=\"toggle close\"><h3 class=\"toggle-head-open\">Answer<i class=\"fa fa-angle-up\"><\/i><\/h3><h3 class=\"toggle-head-close\">Answer<i class=\"fa fa-angle-down\"><\/i><\/h3><div class=\"toggle-content\">\n\t\t\t<strong>1.5 x 10^5 sec<\/strong>\n\t\t\t<\/div><\/div>\n<p><strong><span style=\"color: #ff6600;\">Question#23<\/span>: The value of the steady current, which when flowing through the same resistor produces heat at the same rate as the mean rate of heat produced by the alternating current is______.<\/strong><\/p>\n<ul>\n<li>Average current<\/li>\n<li>Sinusoidal Current<\/li>\n<li>r.m.s current<\/li>\n<li>Net current<\/li>\n<\/ul>\n<div class=\"clear\"><\/div><div class=\"toggle close\"><h3 class=\"toggle-head-open\">Answer<i class=\"fa fa-angle-up\"><\/i><\/h3><h3 class=\"toggle-head-close\">Answer<i class=\"fa fa-angle-down\"><\/i><\/h3><div class=\"toggle-content\">\n\t\t\t<strong>Sinusoidal Current<\/strong>\n\t\t\t<\/div><\/div>\n<p><strong><span style=\"color: #ff6600;\">Question#24<\/span>: To find the r.m.s value of and alternating current mathematically, we need to have_____.<\/strong><\/p>\n<ul>\n<li>Mean value of I<sup>2<\/sup><\/li>\n<li>Square root of mean value of I<sup>2<\/sup><\/li>\n<li>Square root of I<sup>2<\/sup><\/li>\n<li>Square of I\/2<\/li>\n<\/ul>\n<div class=\"clear\"><\/div><div class=\"toggle close\"><h3 class=\"toggle-head-open\">Answer<i class=\"fa fa-angle-up\"><\/i><\/h3><h3 class=\"toggle-head-close\">Answer<i class=\"fa fa-angle-down\"><\/i><\/h3><div class=\"toggle-content\">\n\t\t\t<strong>Square root of I<sup>2<\/sup><\/strong>\n\t\t\t<\/div><\/div>\n<p><strong><span style=\"color: #ff6600;\">Question#25<\/span>: An alternating current of r.m.s value of 4.0 A and frequency 50 Hz flows in a circuit containing 10 ohm resistor. The peak current is then_____.<\/strong><\/p>\n<ul>\n<li>20A<\/li>\n<li>20.66A<\/li>\n<li>6.66A<\/li>\n<li>5.66A<\/li>\n<\/ul>\n<div class=\"clear\"><\/div><div class=\"toggle close\"><h3 class=\"toggle-head-open\">Answer<i class=\"fa fa-angle-up\"><\/i><\/h3><h3 class=\"toggle-head-close\">Answer<i class=\"fa fa-angle-down\"><\/i><\/h3><div class=\"toggle-content\">\n\t\t\t<strong>20A<\/strong>\n\t\t\t<\/div><\/div>\n<p><strong><span style=\"color: #ff6600;\">Question#26<\/span>: An alternating Current of r.m.s value of 2A and a steady direct current I flowing through identical resistors dissipate heat at the same rate. What is the current I?<\/strong><\/p>\n<ul>\n<li>2A<\/li>\n<li>\u221a2\u00a0 A<\/li>\n<li>1A<\/li>\n<li>2\u221a2 A<\/li>\n<\/ul>\n<div class=\"clear\"><\/div><div class=\"toggle close\"><h3 class=\"toggle-head-open\">Answer<i class=\"fa fa-angle-up\"><\/i><\/h3><h3 class=\"toggle-head-close\">Answer<i class=\"fa fa-angle-down\"><\/i><\/h3><div class=\"toggle-content\">\n\t\t\t<strong>2A<\/strong>\n\t\t\t<\/div><\/div>\n<p><strong><span style=\"color: #ff6600;\">Question#27<\/span>: An A.C current is represented by the equation I=I<sub>o <\/sub>sin w t, which of the following equation represents an alternating current of frequency and amplitude twice of the above current?<\/strong><\/p>\n<ul>\n<li>I=2 I<sub>o<\/sub>sin (w t\/2)<\/li>\n<li>I=W I<sub>o <\/sub>sin (2wt)<\/li>\n<li>I=2I sinwt<\/li>\n<li>I=I<sub>o <\/sub>sin(2wt)<\/li>\n<\/ul>\n<div class=\"clear\"><\/div><div class=\"toggle close\"><h3 class=\"toggle-head-open\">Answer<i class=\"fa fa-angle-up\"><\/i><\/h3><h3 class=\"toggle-head-close\">Answer<i class=\"fa fa-angle-down\"><\/i><\/h3><div class=\"toggle-content\">\n\t\t\t<strong>I=I<sub>o <\/sub>sin(2wt)<\/strong>\n\t\t\t<\/div><\/div>\n<p><strong>\u00a0<span style=\"color: #ff6600;\">Question#28<\/span>: In pure resistor circuit, the voltage and current are______.<\/strong><\/p>\n<ul>\n<li>Lagging each other<\/li>\n<li>They are at 90<sup>o<\/sup> phase difference<\/li>\n<li>They have zero phase difference<\/li>\n<li>No phase difference<\/li>\n<\/ul>\n<div class=\"clear\"><\/div><div class=\"toggle close\"><h3 class=\"toggle-head-open\">Answer<i class=\"fa fa-angle-up\"><\/i><\/h3><h3 class=\"toggle-head-close\">Answer<i class=\"fa fa-angle-down\"><\/i><\/h3><div class=\"toggle-content\">\n\t\t\t<strong>Lagging each other<\/strong>\n\t\t\t<\/div><\/div>\n<p><strong><span style=\"color: #ff6600;\">Question#29<\/span>: The power factor of an AC circuit has the value<\/strong><\/p>\n<ul>\n<li>Unity when the circuit contains only an inductance<\/li>\n<li>Unity when the circuit contains only A resistance<\/li>\n<li>Unity when the circuit contains only resistance and capacitor<\/li>\n<li>Unity when the circuit contains only a capacitance<\/li>\n<\/ul>\n<div class=\"clear\"><\/div><div class=\"toggle close\"><h3 class=\"toggle-head-open\">Answer<i class=\"fa fa-angle-up\"><\/i><\/h3><h3 class=\"toggle-head-close\">Answer<i class=\"fa fa-angle-down\"><\/i><\/h3><div class=\"toggle-content\">\n\t\t\t<strong>Unity when the circuit contains only a capacitance<\/strong>\n\t\t\t<\/div><\/div>\n<p><strong><span style=\"color: #ff6600;\">Question#30<\/span>: In capacitive circuit, the current __________.<\/strong><\/p>\n<ul>\n<li>Lags behind voltage by \u03c0\/2<\/li>\n<li>Is in phase with the voltage<\/li>\n<li>Opposite\u00a0 in phase of voltage by \u03c0<\/li>\n<li>Leads forward the voltage by \u03c0\/2<\/li>\n<\/ul>\n<div class=\"clear\"><\/div><div class=\"toggle close\"><h3 class=\"toggle-head-open\">Answer<i class=\"fa fa-angle-up\"><\/i><\/h3><h3 class=\"toggle-head-close\">Answer<i class=\"fa fa-angle-down\"><\/i><\/h3><div class=\"toggle-content\">\n\t\t\t<strong>Opposite\u00a0 in phase of voltage by <\/strong><strong>\u03c0<\/strong>\n\t\t\t<\/div><\/div>\n<p><strong><span style=\"color: #ff6600;\">Question#31<\/span>: A 100 <\/strong><strong>\u00b5F capacitor with 12V source in series having frequency 50 Hz, will offer a capacitive resistance of about_____.<\/strong><\/p>\n<ul>\n<li>32ohm<\/li>\n<li>60 ohm<\/li>\n<li>50 ohm<\/li>\n<li>100 ohm<\/li>\n<\/ul>\n<div class=\"clear\"><\/div><div class=\"toggle close\"><h3 class=\"toggle-head-open\">Answer<i class=\"fa fa-angle-up\"><\/i><\/h3><h3 class=\"toggle-head-close\">Answer<i class=\"fa fa-angle-down\"><\/i><\/h3><div class=\"toggle-content\">\n\t\t\t<strong>100 ohm<\/strong>\n\t\t\t<\/div><\/div>\n<p><strong><span style=\"color: #ff6600;\">Question#32<\/span>: If a glass plate is inserted in between the plate of a capacitor in series with a lighted bulb, the brightness of the bulb______.<\/strong><\/p>\n<ul>\n<li>Remains the same<\/li>\n<li>Brightness increases<\/li>\n<li>Brightness decreases<\/li>\n<li>No light<\/li>\n<\/ul>\n<div class=\"clear\"><\/div><div class=\"toggle close\"><h3 class=\"toggle-head-open\">Answer<i class=\"fa fa-angle-up\"><\/i><\/h3><h3 class=\"toggle-head-close\">Answer<i class=\"fa fa-angle-down\"><\/i><\/h3><div class=\"toggle-content\">\n\t\t\t<strong>Brightness increases<\/strong>\n\t\t\t<\/div><\/div>\n<p><strong><span style=\"color: #ff6600;\">Question#33<\/span>: A pure variable resistor is connected in series with a pure capacitor in series with a pure capacitor of fixed capacitance. The impedance of the circuit______.<\/strong><\/p>\n<ul>\n<li>Remains the same<\/li>\n<li>Becomes infinite<\/li>\n<li>Becomes zero<\/li>\n<li>Increases<\/li>\n<\/ul>\n<div class=\"clear\"><\/div><div class=\"toggle close\"><h3 class=\"toggle-head-open\">Answer<i class=\"fa fa-angle-up\"><\/i><\/h3><h3 class=\"toggle-head-close\">Answer<i class=\"fa fa-angle-down\"><\/i><\/h3><div class=\"toggle-content\">\n\t\t\t<strong>Becomes zero<\/strong>\n\t\t\t<\/div><\/div>\n<p><strong><span style=\"color: #ff6600;\">Question#34<\/span>: A wire of resistance R is coiled inductively so that its inductance is L. The impedance of the coil at a frequency of f is _______.<\/strong><\/p>\n<ul>\n<li>(R+2\u03c0 fL)<sup>1\/2<\/sup><\/li>\n<li>R+1\/2\u03c0f L<\/li>\n<li>(R<sup>2<\/sup>+f<sup>2<\/sup>L<sup>2<\/sup>)<sup>1\/2<\/sup><\/li>\n<li>(R<sup>2<\/sup>+4\u03c0<sup>2<\/sup>f<sup>2<\/sup>L<sup>2<\/sup>)<sup>1\/2<\/sup><\/li>\n<\/ul>\n<div class=\"clear\"><\/div><div class=\"toggle close\"><h3 class=\"toggle-head-open\">Answer<i class=\"fa fa-angle-up\"><\/i><\/h3><h3 class=\"toggle-head-close\">Answer<i class=\"fa fa-angle-down\"><\/i><\/h3><div class=\"toggle-content\">\n\t\t\t<strong>(R<sup>2<\/sup>+f<sup>2<\/sup>L<sup>2<\/sup>)<sup>1\/2<\/sup><\/strong>\n\t\t\t<\/div><\/div>\n<p><strong><span style=\"color: #ff6600;\">Question#35<\/span>: Ammeter connected in an AC circuit measures________. <\/strong><\/p>\n<ul>\n<li>The exact value of the current<\/li>\n<li>rms value of current<\/li>\n<li>The net value of the current<\/li>\n<li>The peak value of the current<\/li>\n<\/ul>\n<div class=\"clear\"><\/div><div class=\"toggle close\"><h3 class=\"toggle-head-open\">Answer<i class=\"fa fa-angle-up\"><\/i><\/h3><h3 class=\"toggle-head-close\">Answer<i class=\"fa fa-angle-down\"><\/i><\/h3><div class=\"toggle-content\">\n\t\t\t<strong>Net value of current<\/strong>\n\t\t\t<\/div><\/div>\n<p><strong><span style=\"color: #ff6600;\">Question#36<\/span>: When a pure inductor of inductance L and a pure capacitor of capacitance C are connected in parallel to a sinusoidal potential difference V, then potential difference across both L and C will be______.<\/strong><\/p>\n<ul>\n<li>Same<\/li>\n<li>Different<\/li>\n<li>At L will be more than at C<\/li>\n<li>At L will be less than at C<\/li>\n<\/ul>\n<div class=\"clear\"><\/div><div class=\"toggle close\"><h3 class=\"toggle-head-open\">Answer<i class=\"fa fa-angle-up\"><\/i><\/h3><h3 class=\"toggle-head-close\">Answer<i class=\"fa fa-angle-down\"><\/i><\/h3><div class=\"toggle-content\">\n\t\t\t<strong>At L will be less than at C<\/strong>\n\t\t\t<\/div><\/div>\n<p><strong><span style=\"color: #ff6600;\">Question#37<\/span>: An ideal choke would be_______.<\/strong><\/p>\n<ul>\n<li>Pure capacitor<\/li>\n<li>Pure conductor<\/li>\n<li>Pure resistor<\/li>\n<li>Combination of inductor and capacitor<\/li>\n<\/ul>\n<div class=\"clear\"><\/div><div class=\"toggle close\"><h3 class=\"toggle-head-open\">Answer<i class=\"fa fa-angle-up\"><\/i><\/h3><h3 class=\"toggle-head-close\">Answer<i class=\"fa fa-angle-down\"><\/i><\/h3><div class=\"toggle-content\">\n\t\t\t<strong>Pure conductor<\/strong>\n\t\t\t<\/div><\/div>\n<p><strong><span style=\"color: #ff6600;\">Question#38<\/span>: What is the self-inductance of a coil in which an induced emf of 2V is set up when the current changes at the rate of 4 As<sup>-1<\/sup>?<\/strong><\/p>\n<ul>\n<li>0.5mH<\/li>\n<li>0.5H<\/li>\n<li>2.0H<\/li>\n<li>8.0H<\/li>\n<\/ul>\n<div class=\"clear\"><\/div><div class=\"toggle close\"><h3 class=\"toggle-head-open\">Answer<i class=\"fa fa-angle-up\"><\/i><\/h3><h3 class=\"toggle-head-close\">Answer<i class=\"fa fa-angle-down\"><\/i><\/h3><div class=\"toggle-content\">\n\t\t\t<strong>0.5H<\/strong>\n\t\t\t<\/div><\/div>\n<p><strong><span style=\"color: #ff6600;\">Question#39<\/span>: The frequency of a circuit consisting of a capacitance C and a resistor R is_________.<\/strong><\/p>\n<ul>\n<li>C\/R<\/li>\n<li>R\/C<\/li>\n<li>1\/RC<\/li>\n<li>1\/R<\/li>\n<\/ul>\n<div class=\"clear\"><\/div><div class=\"toggle close\"><h3 class=\"toggle-head-open\">Answer<i class=\"fa fa-angle-up\"><\/i><\/h3><h3 class=\"toggle-head-close\">Answer<i class=\"fa fa-angle-down\"><\/i><\/h3><div class=\"toggle-content\">\n\t\t\t<strong>1\/RC<\/strong>\n\t\t\t<\/div><\/div>\n<p><strong><span style=\"color: #ff6600;\">Question#40<\/span>: A 10ohm electric heater is connected to a 220V, 50Hz mains supply. What is the peak value of the potential difference across the heater element?<\/strong><\/p>\n<ul>\n<li>220V<\/li>\n<li>220\/\u221a2 V<\/li>\n<li>110V<\/li>\n<li>220\u221a2 V<\/li>\n<\/ul>\n<div class=\"clear\"><\/div><div class=\"toggle close\"><h3 class=\"toggle-head-open\">Answer<i class=\"fa fa-angle-up\"><\/i><\/h3><h3 class=\"toggle-head-close\">Answer<i class=\"fa fa-angle-down\"><\/i><\/h3><div class=\"toggle-content\">\n\t\t\t<strong>220V<\/strong>\n\t\t\t<\/div><\/div>\n\n<div style=\"font-size: 0px; height: 0px; line-height: 0px; margin: 0; padding: 0; clear: both;\"><\/div>","protected":false},"excerpt":{"rendered":"<p>Here you can get the Physics Chapter 16 Alternating Current MCQs 2nd Year for the Entry Test preparations. The current which is produced by a voltage source whose polarity keeps on reversing is called Alternating Current. There are many AC circuits used to supply Alternating current. In a capacitor, direct current cannot flow. So alternating &hellip;<\/p>\n","protected":false},"author":2,"featured_media":375,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[3],"tags":[],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/talib.pk\/test-preparation\/wp-json\/wp\/v2\/posts\/200"}],"collection":[{"href":"https:\/\/talib.pk\/test-preparation\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/talib.pk\/test-preparation\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/talib.pk\/test-preparation\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/talib.pk\/test-preparation\/wp-json\/wp\/v2\/comments?post=200"}],"version-history":[{"count":0,"href":"https:\/\/talib.pk\/test-preparation\/wp-json\/wp\/v2\/posts\/200\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/talib.pk\/test-preparation\/wp-json\/wp\/v2\/media\/375"}],"wp:attachment":[{"href":"https:\/\/talib.pk\/test-preparation\/wp-json\/wp\/v2\/media?parent=200"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/talib.pk\/test-preparation\/wp-json\/wp\/v2\/categories?post=200"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/talib.pk\/test-preparation\/wp-json\/wp\/v2\/tags?post=200"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}