Answer:
the work done by gravity on the boy is 604.62 J
Explanation:
Given;
distance the boy slides, d = 3 m
angle of inclination of the playground, θ = 40⁰
mass of the boy, m = 32 kg
The vertical height, h, above the ground through which the boy falls represents the height of the triangle which is the opposite side.
The distance through which the boy slides, d, represents the hypotenuse side of the right triangle.

The work done by gravity on the boy is calculated as;
W = P.E = mgh
= 32kg x 9.8m/s² x 1.928m
= 604.62 J
Therefore, the work done by gravity on the boy is 604.62 J
The impulse J is equal to the magnitude of the force applied to the cannonball times the time it is applied:

But the impulse is also equal to the change in momentum of the cannonball:

If we put the two equations together, we find

And since we know the magnitude of the average force and the time, we can calculate the change in momentum:
It is an important part of many cells and processes such as amino acids, proteins and even our DNA. It is also needed to make chlorophyll in plants, which is used in photosynthesis to make their food.
Hope this helps! ;)
Answer:
2156 J
Explanation:
From the question,
Work done = Combined mass of the bucket and water×height×gravity.
W = (M+m)hg............................. Equation 1
Where M = mass of water, m = mass of the bucket, h = height, g = acceleration due to gravity.
Given: M = 20 kg, m = 2 kg, h = 10 m
Constant: g = 9.8 m/s²
Substitute these value into equation 1
W = (20+2)×10×9.8
W = 22×98
W = 2156 J
Earth's protective magnetic bubble, called the magnetosphere, deflects most solar particles, but in the absence of atmospheric layer, Polyethylene is a good shielding material because it has high hydrogen content, and hydrogen atoms are good at absorbing and dispersing radiation.
The Earth’s atmospheres are kept in place by gravity. The air near the ground is pulled on by gravity and compressed by the air higher in the sky. This causes the air near the ground to be denser and creating different layers with different qualities in which are the atmosphere.
Hope that helps ^^