1

The angle between the direction of the earth's magnetic field and the horizontal is called the

A

angle of deviation

B

magnetic declination

C

magnetic meridian

D

angle of dip

CORRECT OPTION:
d

2

Calculate the force acting on an electron of charge 1.6 x 10^{-19}C placed in an electric field of intensity 10^{8}Vm^{-1}

A

1.6 x 10^{-11}N

B

1.6 x 10^{-14}N

C

1.6 x 10^{-16}N

D

1.0 x 10^{-16}N

CORRECT OPTION:
a

F = EQ

1.6 x 10^{-19} x 10^{8}

= 1.6 x 10^{-11}N

1.6 x 10

= 1.6 x 10

3

When an ebolite rod is rubbed with fur, it has

A

no charge at all

B

a negative charge

C

a positive charge

D

negative and positive charges

CORRECT OPTION:
b

4

Which of the following factors has no effect on the e.m.f. of a primary cell?

A

temperature

B

size of the cell

C

nature of the plate

D

nature of the electrolyte

CORRECT OPTION:
b

5

A wire of length 15m made of a material of resistivity 1.8 x 10^{-6}\(\Omega\)m has a resistance of 0.27\(\Omega\). Determine the area of the wire

A

1.5 x 10^{-4}m^{2}

B

1.0 x 10^{-4}m^{2}

C

2.7 x 10^{-5}m^{2}

D

7.3 x 10^{-6}m^{2}

CORRECT OPTION:
b

Resistivity = \(\frac{\text {Resiatance x Area}}{length}\)

1.6 x 10^{-6} = \(\frac{15 \times Area}{0.27}\)

Area = 1.0 x 10^{-4}m^{2}

1.6 x 10

Area = 1.0 x 10

6

A 5-v battery is connected across the plates of a 2.0\(\mu\)F uncharged parallel plate capacitor. The charge on the capacitor after a long time is

A

2.5\(\mu\)C

B

10.0\(\mu\)C

C

20.0\(\mu\)C

D

50.0\(\mu\)C

CORRECT OPTION:
b

Q = cv

= 2 x 10^{-6} x 5

= 10 x 10^{-6}C

= 10.0\(\mu\)C

= 2 x 10

= 10 x 10

= 10.0\(\mu\)C

7

Which of the following apparatus will require the smallest fuse rating for its protection?

A

60W, 240V

B

60W, 40V

C

40W, 12V

D

40W, 5V

CORRECT OPTION:
a

I = \(\frac{P}{V}\) = \(\frac{60}{240}\) = 0.25A

I = \(\frac{P}{V}\) = \(\frac{60}{40}\) = 1.5A

I = \(\frac{P}{V}\) = \(\frac{40}{12}\) = 3.3A

I = \(\frac{P}{V}\) = \(\frac{40}{5}\) = 8A

I = \(\frac{P}{V}\) = \(\frac{60}{40}\) = 1.5A

I = \(\frac{P}{V}\) = \(\frac{40}{12}\) = 3.3A

I = \(\frac{P}{V}\) = \(\frac{40}{5}\) = 8A

8

The heat produced in a conductor carrying an electric current is

A

inversely proportional to the current and the resistance

B

directly proportional to the current, resistance and the time

C

inversely proportional to of the resistance, current and the time

D

directly proportional to the square of the current, the resistance and the time

CORRECT OPTION:
d

9

The maximum permissible current through a galvanometer G of internal resistance 10\(\Omega\) is 0.05A. A resistance R is used to convert G into a voltmeter with a maximum reading of 100V. Find the value of R and how it is connected to G

A

20,000 ohms in parallel

B

19,990 ohms in series

C

1990 ohms in series

D

100 ohms in series

CORRECT OPTION:
c

10

In alternating current theory, the units of impedance, r.m.s. voltage and resonance frequency are respectively equal to

A

volt, ampere and hertz

B

ohms, volt and hertz

C

watt, ohms and radian

D

ohms, hertz and joule

CORRECT OPTION:
b

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