# Physics-Magnetism & Electricity at Work (NTSE Stage-1 (State-Level) Scholastic-Aptitude & Language Comprehension): Questions 7 - 12 of 46

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## Question number: 7

» Physics » Magnetism & Electricity at Work

MCQ▾

### Question

Consider the following facts regarding electrons and identify the incorrect statements.

### Choices

Choice (4) Response

a.

Relative charge of an electron is -1

b.

Electron was named by stoney

c.

Mass of an electron is 9.11 x 10- 27 g

d.

Charge of an electron is -1.6 × 10 -19 C

## Question number: 8

» Physics » Magnetism & Electricity at Work

MCQ▾

### Question

A permanent magnet

### Choices

Choice (4) Response

a.

attracts magnetic substances and repels all non-magnetic substances

b.

attracts all substances

c.

attracts only magnetic substances

d.

attracts non-magnetic substances and repels magnetic substances

## Question number: 9

» Physics » Magnetism & Electricity at Work

MCQ▾

### Question

If in the circuit, power dissipation is 150 W, then R is

### Choices

Choice (4) Response

a.

4 Ω

b.

6 Ω

c.

5 Ω

d.

None of the above

## Question number: 10

» Physics » Magnetism & Electricity at Work

MCQ▾

### Question

On applying an external magnetic field to a ferromagnetic substance domains

### Choices

Choice (4) Response

a.

align in the direction opposite to magnetic field

b.

remains unaffected

c.

align in the direction of magnetic field

d.

All of the above

## Question number: 11

» Physics » Magnetism & Electricity at Work

MCQ▾

### Question

A current of 0.5 A is drawn by a filament of an electric bulb for half an hour. What is the amount of electric charge that flows through the circuit?

### Choices

Choice (4) Response

a.

900°C

b.

9°C

c.

5°C

d.

600°C

## Question number: 12

» Physics » Magnetism & Electricity at Work

MCQ▾

### Question

A water heater marked 2 kW, 220 V is connected to a 220 V supply. How long will it take to heat 20 kg of water from 10°C to 30°C? Assume that all the heat is taken up by the water, (specific heat of water = 4200 J kg- 2 C- 2)

### Choices

Choice (4) Response

a.

14min

b.

28 min

c.

41 min

d.

20min