Post Utme Physics Past Questions and Answers

Question 561:

An inductor, $\mathrm{L}=75\mathrm{mH}$ is connected in series to a source of alternating emf of rms value $250\mathrm{V}$ and frequency $50\mathrm{Hz}$. What is the rms value of the current?

A. $21.22\mathrm{A}$
B. $1.69\mathrm{A}$
C. $10.46\mathrm{A}$
D. $5.31\mathrm{A}$
E. $26.53\mathrm{A}$

Question 562:

A series RLC circuit consists of a $75\mathrm{\Omega }$ resistor, a $5.0$ ff capacitor and $a75\mathrm{mH}$ inductor. They are connected across a generator of frequency $250\mathrm{Hz}$ with a rms voltage of $12\mathrm{V}$. Determine the impedance of the circuit.

A. $127.32\mathrm{\Omega }$
B. $117.8\mathrm{\Omega }$
C. $84.51\mathrm{\Omega }$
D. $74.39\mathrm{\Omega }$
E. $75.6\mathrm{\Omega }$

Question 563:

A circuit consists of a $220.0\mathrm{\Omega }$ resistor and a 0.5II inductor connected across a generator that has a frequency of $120\mathrm{Hz}$ and $a$ voltage if $230\mathrm{V}$. Determine the phase angle between the current and the voltage

A. ${59.73}^{\circ }$
B. ${68.38}^{\circ }$
C. ${26.75}^{\circ }$
D. ${30.27}^{\circ }$
E. ${38.21}^{\circ }$

Question 564:

A $2500\mathrm{\Omega }$ resistor and $2.5\mu \mathrm{f}$ capacitors are connected in series across a generator of $60\mathrm{Hz}$ frequency and $121\mathrm{V}$. Determine the power dissipated in the circuit.

A. $2.07\mathrm{W}$
B. $2.25\mathrm{W}$
C. $4.88\mathrm{W}$
D. $4.14\mathrm{W}$
E. $45\mathrm{W}$

Question 565:

A converging lens can be used a magnifying glass if the ____________

A. Object is placed at $F$
B. Object is placed between $F$ and the pole
C. Object is placed at the pole
D. All of the above