# IGCSE Physics Paper-1: Specimen Questions with Answers 83 - 85 of 109

## Question number: 83

Edit
MCQ▾

### Question

A stopwatch is used to note time of a race is shown in figure. How long did the race take?

### Choices

Choice (4) Response

a.

47.0 s

b.

46.0s

c.

46.5s

d.

45.7s

b.

### Explanation

From above figure, we can note down the start time is 0.5 s and end time is 46.5 s. Therefore race time is given as,

## Question number: 84

Edit
MCQ▾

### Question

Find the amount of sample left after 18 hours if the half-life is 8 hours and has 0.37 g of the substance.

### Choices

Choice (4) Response

a.

0.03 g

b.

7.68 g

c.

1.76 g

d.

0.12 g

c.

### Explanation

Here from given data

Formula of half-life is given as,

## Question number: 85

Edit
MCQ▾

### Question

How we find density of a regularly-shaped block?

### Choices

Choice (4) Response

a.

a measuring cylinder and a beaker

b.

a measuring cylinder and a ruler

c.

a balance and a ruler

d.

a balance and a force meter (spring balance)