# IGCSE Physics Paper-1: Specimen Questions with Answers 109 - 111 of 149

## Question 109

### Question

MCQ▾

How can a permanent magnet be demagnetized?

### Choices

Choice (4)

a.

cool the magnet for a long time

b.

heat the magnet

c.

pass a small current through the magnet

d.

leave the magnet in a coil which carries direct current

b.

### Explanation

In permanent magnet alignment of the domain properly unidirectional. To demagnetize the permanent magnet these alignment of the domain should be random. So by heating the magnet domain arranged randomly and it is demagnetized.

## Question 110

### Question

MCQ▾

Vertical cylinder contains some liquid. The height of the tank is known what is required to measure the volume of the tank?

### Choices

Choice (4)

a.

Area

b.

Density

c.

Mass

d.

water level of height (f)

a.

### Explanation

• Volume of the vertical cylinder
• To find out the volume of cylinder it requires both area of the cylinder and the height of the cylinder.
• The height of the cylinder is given in the figure.
• So the required element to find out the volume of the cylinder is area.

## Question 111

### Question

MCQ▾

A diagram shows the timer on a stop clock at the beginning and at the end of experiment. How long did the experiment take?

Choice (4)

a.

50 s

b.

45 s

c.

30 s

d.

35 s