Answer:
option (e) is correct.
Explanation:
mass of adult, M = 81 kg
Gravitational Potential energy of adult, U = 2000 J
Let the height raised is h.
U = mass of adult x g x h
2000 = 81 x 9.8 x h
h = 2.52 m
mass of adult, m = 18 kg
height raised, h = 2.52 m
Potential energy of child, U' = m x g x h
U' = 18 x 2.52 x 9.8 = 444.44 J
Thus, option (e) is correct.
It is the heat required to raise the temperature of the unit mass of a given substance by a given amount (usually one degree).
Answer:
E = 1.45 x 10⁹ J = 1.45 GJ
Explanation:
According to the law of conservation of energy:
Potential Energy Lost by Satellite = Kinetic Energy + Internal Energy
where,
E = Internal Energy = ?
m = mass = 400 kg
g = acceleration due to gravity = 9.81 m/s²
h = height = 500 km = 500000 m
v = speed on ground = 1.6 km/s = 1600 m/s
Therefore,
<u>E = 1.45 x 10⁹ J = 1.45 GJ</u>
Answer: The net force acting on an object is the sum of all the force acting on it, and the net force of an object is zero. I f the forces acting on it tend to cancel each other. For example you are sit in a chair, the earth's gravity is pulling you down, but the chair is pushing you up with an equal amount of force.
There is my answer from my notebook .I hope its good :)
Explanation:
Every atom has no overall charge (neutral). This is because they contain equal numbers of positive protons and negative electrons. These opposite charges cancel each other out making the atom neutral.