1. A ball is thrown vertically upwards with a velocity of 49m/s. Calculate(adsbygoogle = window.adsbygoogle || []).push({});

a) The maximum height to which it rises

b) The total time it takes to return to the surface of the earth.

2. A certain force exerted for 1.2 seconds increases the speed of an object

from 1.8m/s to 4.2m/s. Later the same force is applied for 2 seconds. How

much does the speed change in 2 seconds?

3. A motorboat starting from rest on a lake accelerates in a straight line

at a constant rate of three metres per second square for 8 seconds. How

far does the boat travel during this time?

4. a) Why are double tyres provided at the rear wheels of a truck?

b) A man at the top of a tower throws an object horizontally

whereas he simply drops another. Will these two objects reach

the earth at the same time? Why?

c) Explain why a dead body floats, with its head immersed in

water?

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# Homework Help: Explain why a dead body floats

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