Answer:
fixed pulley: A pulley system in which the pulley is attached to a fixed point and the rope is attached to the object. ... movable pulley: A pulley system in which the pulley is attached to the object; one end of the rope is attached to a fixed point and the other end of the rope is free.
Explanation:
Hi Pupil Here is your answer ::
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1 The shape of the Body
Example : The shape of the ball lying on a floor can be changed by pressing it.
2 Direction of the Body
Example : The direction of motion of moving ball can be changed by hitting it with a bat.
3 The speed of the Body
Example : A ball at rest can be set in motion if force is applied only
4. Size of the Body
Example : The length of a spring tied and on one end can be increased by pulling it.
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Hope this helps .......
Answer:

Explanation:
Since work done is in the form of potential energy, we will use the formula of potential energy here.
We know that,
<h3>P.E. = mgh </h3>
Where,
m = mass = 20 kg
g = acceleration due to gravity = 10 m/s²
h = vertical height = 20 m
So,
<h3>Work done = mgh</h3>
Work done = (20)(10)(20)
Work done = 4000 joules
Work done = 4 kJ
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