12th Physics weekly Test -1 ( Electromagnetic Induction And Alternating Current )

St. Britto Hr. Sec. School - Madurai

12th Physics weekly Test -1 ( Electromagnetic Induction And Alternating Current )-Aug 2020

Time : 1.30 Hours

Part - A

Multiple Choice Question - Answer All Question

\(\frac{20}{\pi^2}H\)inductor is connected to a capacitor of capacitance C. The value of C in order to impart maximum power at 50 Hz is

50 μF
0.5 μF
500 μF
5 μF

For an ideal transformer __________

E_pI_p = E_sI_s
E_pE_s = I_p
E_pE_s= I_s
I_pI_s = E_sI_s

The unit of impedance is ________________

mho-metre^-1
ohm
ohm-metre
mho-metre

A circular coil with a cross-sectional area of 4 cm2 has 10 turns. It is placed at the centre of a long solenoid that has 15 turns/cm and a cross-sectional area of 10 cm2. The axis of the coil coincides with the axis of the solenoid. What is their mutual inductance?

7.54 μH
8.54 μH
9.54 μH
10.54 μH

If two coils are wound on a soft iron core the mutual induction is

small
very large
infinity
zero

Th e fl ux linked with a coil at any instant t is given by \(\Phi\)_B =10t²−50t+ 250 . The induced emf at t = 3s is

−190 V
−10 V
10 V
190 V

Energy or workdone is stored in an inductor as

electrical energy
magnetic potential energy
electrical potential energy
heat energy

Copper loss is energy loss in the form of _______
light

heat

sound

hysteresis
The instantaneous values of alternating current and voltage in a circuit are \(i=\frac { 1 }{ \sqrt { 2 } } sin\left( 100\pi t \right) \) A and v=\(=\frac { 1 }{ \sqrt { 2 } } sin\left( 100\pi t+\frac { \pi }{ 3 } \right) V.\)The average power in watts consumed in the circuit is
\(\frac{1}{4}\)

\(\frac{\sqrt3}{4}\)

\(\frac{1}{2}\)

\(\frac{1}{8}\)

Eddy currents was first observed by

Foucault
Newton
Faraday
Fleming

In a series RL circuit, the resistance and inductive reactance are the same. Then the phase difference between the voltage and current in the circuit is

\(\frac{\pi}{4}\)
\(\frac{\pi}{2}\)
\(\frac{\pi}{6}\)
zero

Part - B

Generic 2 - Answer All Question

What is meant by mutual induction?

What for an inductor is used? Give some examples.

How will you define RMS value of an alternating current?

What are LC oscillations?
How will you define Q-factor?

List out the advantages of stationary armature-rotating field system of AC generator.

Part - C

Generic 3 - Answer All Question

The current flowing in the first coil changes from 2 A to 10 A in 0.4 sec. Find the mutual inductance between two coils if an emf of 60 mV is induced in the second coil. Also determine the induced emf in the second coil if the current in the first coil is changed from 4 A to 16 A in 0.03 sec. Consider only the magnitude of induced emf.
A straight conducting wire is dropped horizontally from a certain height with its length along east – west direction. Will an emf be induced in it? Justify your answer.

What is Phasort and How to draw phasor diagram.

Prove that energy is conserved during electromagnetic induction.

What do you understand by self-inductance of a coil? Give its physical significance.

Mention the various energy losses in a transformer

Part - D

Generic 5 - Answer All Question

A long solenoid having 400 turns per cm carries a current 2A. A 100 turn coil of cross-sectional area 4 cm² is placed co-axially inside the solenoid so that the coil is in the field produced by the solenoid. Find the emf induced in the coil if the current through the solenoid reverses its direction in 0.04 sec.

What is alternating current? Write an expression for its instantaneous value and write the frequency of DC.
A coil of 200 turns carries a current of 4 A. If the magnetic flux through the coil is 6 x 10^-5 Wb, find the magnetic energy stored in the medium surrounding the coil.

Determine the self-inductance of 4000 turn air-core solenoid of length 2m and diameter 0.04 m.

Comment

Add Comment

InstaQB

Institutions

12th Standard English Medium

12th Standard Tamil Medium

11th Standard English Medium

11th Standard Tamil Medium

10th Standard English Medium

9th Standard English Medium

8th Standard English Medium

7th Standard English Medium

Class XII

Class XI

12Th Standard

11Th Standard

10Th Standard

9Th Standard

12th Physics weekly Test -1 ( Electromagnetic Induction And Alternating Current )

St. Britto Hr. Sec. School - Madurai

12th Physics weekly Test -1 ( Electromagnetic Induction And Alternating Current )-Aug 2020

Part - A

Multiple Choice Question - Answer All Question

\(\frac{20}{\pi^2}H\)inductor is connected to a capacitor of capacitance C. The value of C in order to impart maximum power at 50 Hz is

For an ideal transformer __________

The unit of impedance is ________________

A circular coil with a cross-sectional area of 4 cm2 has 10 turns. It is placed at the centre of a long solenoid that has 15 turns/cm and a cross-sectional area of 10 cm2. The axis of the coil coincides with the axis of the solenoid. What is their mutual inductance?

If two coils are wound on a soft iron core the mutual induction is

Th e fl ux linked with a coil at any instant t is given by \(\Phi\)B =10t2−50t+ 250 . The induced emf at t = 3s is

Energy or workdone is stored in an inductor as

Copper loss is energy loss in the form of _______

The instantaneous values of alternating current and voltage in a circuit are \(i=\frac { 1 }{ \sqrt { 2 } } sin\left( 100\pi t \right) \) A and v=\(=\frac { 1 }{ \sqrt { 2 } } sin\left( 100\pi t+\frac { \pi }{ 3 } \right) V.\)The average power in watts consumed in the circuit is

Eddy currents was first observed by

In a series RL circuit, the resistance and inductive reactance are the same. Then the phase difference between the voltage and current in the circuit is

Part - B

Generic 2 - Answer All Question

What is meant by mutual induction?

What for an inductor is used? Give some examples.

How will you define RMS value of an alternating current?

What are LC oscillations?

How will you define Q-factor?

List out the advantages of stationary armature-rotating field system of AC generator.

Part - C

Generic 3 - Answer All Question

A straight conducting wire is dropped horizontally from a certain height with its length along east – west direction. Will an emf be induced in it? Justify your answer.

What is Phasort and How to draw phasor diagram.

Prove that energy is conserved during electromagnetic induction.

What do you understand by self-inductance of a coil? Give its physical significance.

Mention the various energy losses in a transformer

Part - D

Generic 5 - Answer All Question

What is alternating current? Write an expression for its instantaneous value and write the frequency of DC.

A coil of 200 turns carries a current of 4 A. If the magnetic flux through the coil is 6 x 10-5 Wb, find the magnetic energy stored in the medium surrounding the coil.

Determine the self-inductance of 4000 turn air-core solenoid of length 2m and diameter 0.04 m.

Comment

Other Study material

12th Physics Monthly Test - 3 ( Magnetism and magn

12th Physics Monthly Test - 1 ( Electromagnetic In

12th Physics Monthly Test - 2 (Current Electricity

12th Physics Monthly Test - 3 ( Current Electricit

12th Physics Monthly Test - 1 ( Magnetism and magn

12th Physics Monthly Test - 2 ( Magnetism and magn

12th Physics weekly Test - 1 ( Communication Syste

12th Physics weekly Test - 2 ( Communication Syste

12th Physics weekly Test - 1 ( Recent Developments

12th Physics weekly Test - 2 ( Recent Developments

12th Physics Monthly Test - 1 ( Electrostatics )

12th Physics Monthly Test - 2 ( Electrostatics )

12th Physics Monthly Test - 2 ( Electrostatics )

12th Physics Monthly Test - 3 ( Electrostatics )

12th Physics Monthly Test - 1( Current Electricity

Tamilnadu Stateboardszs - Class

Th e fl ux linked with a coil at any instant t is given by \(\Phi\)_B =10t²−50t+ 250 . The induced emf at t = 3s is

A coil of 200 turns carries a current of 4 A. If the magnetic flux through the coil is 6 x 10^-5 Wb, find the magnetic energy stored in the medium surrounding the coil.