GCSE Questions: Forces
Q32. Hailstones are small balls of ice.
Hailstones form in clouds and fall to the ground.
The photo shows different-sized hailstones.
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(a) A hailstone falls from a cloud and accelerates.
(i) Why does the hailstone accelerate?
[1 mark]
(ii) The hailstone stops accelerating and reaches terminal velocity.
Explain why the hailstone reaches terminal velocity.
[3 marks]
(b) The kinetic energy of a hailstone is measured in joules.
Which of the following is the same as 1 joule?
(c) A scientist investigated how the mass of hailstones affects their terminal velocity.
The graph below shows the results of her investigation.
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(i) Tick one of the following to explain why terminal velocity increases with mass:
As mass increases the cross-sectional surface area of a hailstone increases. |
|
As mass increases the volume of a hailstone increases. |
|
As mass increases the weight of a hailstone increases. |
|
[1 mark]
(ii) Explain the difference in the maximum kinetic energy of a hailstone with a mass of
10 g and a hailstone with a mass of 20 g.
[3 marks]
(iii) A hailstone hit the ground at its terminal velocity of 25 m/s.
The hailstone took 0.060 s to stop moving.
Using information from graph above, determine the average force on the hailstone as it hits the ground.
[3 marks]
[12 Marks TOTAL]