Answer:
Lightning is a process that occurs when the positive and negative charges present in the cloud build up in such a manner that a spark of lightning occurs between the two of them in the cloud. ... A metal rod placed on top of a building to protect it from a lightning strike is known as a lightning conductor.
Explanation:
It’s because conductors have nearly zero resistance to the flow of electrons that go through them. This leaves the electrons free to move and current can travel with full strength.
Answer:
stars share a gravitational force with the galaxy while nearby galaxies do not share a gravitational field.
Explanation:
stars will not collide because they are bound by a gravitational orbit around the galaxy
Answer:
(a) work required to lift the object is 1029 J
(b) the gravitational potential energy gained by this object is 1029 J
Explanation:
Given;
mass of the object, m = 35 kg
height through which the object was lifted, h = 3 m
(a) work required to lift the object
W = F x d
W = (mg) x h
W = 35 x 9.8 x 3
W = 1029 J
(b) the gravitational potential energy gained by this object is calculated as;
ΔP.E = Pf - Pi
where;
Pi is the initial gravitational potential energy, at initial height (hi = 0)
ΔP.E = (35 x 9.8 x 3) - (35 x 9.8 x 0)
ΔP.E = 1029 J
