Answer:
U = 1000 J
Explanation:
By the conservation of energy, potential energy is converted into kinetic energy when the ball falls from a height.
U = Energy (in Joules)
m = mass (in kg)
v = velocity in (m/s)
g = acceleration due to gravity (in m/s^2)
h = height (in m)
Let's use 
as we have the values given.
Answer:
A nuclear winter is a climatic phenomenon that would follow the detonation of several atomic bombs in the event that a nuclear war broke out. These bombs would cause firestorms that would raise smoke, dust and particles into the atmosphere that would end up in the stratosphere and eventually spread throughout the globe.
Explanation:
That idea is far fetched, because even though those same particles would absorb sunlight, it would raise the temperature in the stratosphere and cause a decrease in temperature in the Earth's layer. Unable to seep the sun's rays, many plant species would die and this would affect the entire food chain.
In addition, that temperature rise in the stratosphere would destroy part of the ozone layer, causing greater exposure to ultraviolet rays. This would end up affecting health and further damaging plant species.
This is true. There is a downward force on the table that stabilizes the rock to stay there.
Explanation:
ω = 30 rev × (2π rad/rev) / (6 sec)
ω = 10π rad/s
ω ≈ 31.4 rad/s
