NOOTAN ISC PHYSICS Class 12 Part-1>Chapter 5 - Electric Resistance and Ohm's Law>QUESTIONS>Q 16

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12th ICSE

IMPORTANT

Earn 100

Two copper wires $A$ and $B$ of equal masses are taken. The length of $A$ is double the length of $B$ . If the resistance of the wire $B$ . If the resistance of wire A is $160 Ω$ , then calculate the resistance of wire B.

Important Questions on Electric Resistance and Ohm's Law

HARD

12th ICSE

IMPORTANT

NOOTAN ISC PHYSICS Class 12 Part-1>Chapter 5 - Electric Resistance and Ohm's Law>QUESTIONS>Q 17

A

200 V

bulb takes a current of

0.2 A

. The length of its filament is

22 cm

and the specific resistance of the material of the filament is

7 \times 10^{- 5} Ω - cm

. Find the radius of the filament

(π = \frac{22}{7})

.

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12th ICSE

IMPORTANT

NOOTAN ISC PHYSICS Class 12 Part-1>Chapter 5 - Electric Resistance and Ohm's Law>QUESTIONS>Q 18

A rectangular block of iron has dimensions $1.2 cm \times 1.2 cm \times 15 cm$ . Compute the resistance of the block between the two square ends. The specific resistance of iron at room temperature is $9.68 \times 10^{- 8} Ω m$ .

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12th ICSE

IMPORTANT

NOOTAN ISC PHYSICS Class 12 Part-1>Chapter 5 - Electric Resistance and Ohm's Law>QUESTIONS>Q 18

A rectangular block of iron has dimensions

1.2 cm \times 1.2 cm \times 15 cm

. Compute the resistance of the block between the two opposite rectangular faces. The specific resistance of iron at room temperature is

9.68 \times 10^{- 8} Ω m

.

HARD

12th ICSE

IMPORTANT

NOOTAN ISC PHYSICS Class 12 Part-1>Chapter 5 - Electric Resistance and Ohm's Law>QUESTIONS>Q 19

Two wires of different materials; of length

50 cm

and

75 cm

and respective diameters

0.2 mm

and

0.1 mm

, have resistances of

0.8 Ω

and

1.5 Ω

respectively. What is the ratio of the specific resistances of the materials?

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12th ICSE

IMPORTANT

NOOTAN ISC PHYSICS Class 12 Part-1>Chapter 5 - Electric Resistance and Ohm's Law>QUESTIONS>Q 20

A

100 W - 200 V

bulb is connected to a

110 V DC

source. Calculate the power consumed by the bulb.

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12th ICSE

IMPORTANT

NOOTAN ISC PHYSICS Class 12 Part-1>Chapter 5 - Electric Resistance and Ohm's Law>QUESTIONS>Q 21

The maximum power dissipated in a

10000 Ω

resistor is

1 W

. What is the maximum current?

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12th ICSE

IMPORTANT

NOOTAN ISC PHYSICS Class 12 Part-1>Chapter 5 - Electric Resistance and Ohm's Law>QUESTIONS>Q 22

How much charge flows through a

250 V - 1000 W

heater in one minute?

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12th ICSE

IMPORTANT

NOOTAN ISC PHYSICS Class 12 Part-1>Chapter 5 - Electric Resistance and Ohm's Law>QUESTIONS>Q 23

Compute the voltage drop across a

2 kW

electric heater element whose resistance when hot is

20 Ω

.