Answer:
The first law of thermodynamics. In brief, energy can neither be created nor destroyed. However, energy may be converted from one form to another.
Explanation:
A basic electrical solar fan comes in two parts: a solar panel connected to an electrical motor. The solar panel converts solar energy to electricity; the electrical motor converts electricity to mechanical energy, which causes the blades to turn.
This energy conversion is possible because of the first law of thermodynamics. This law states that the total energy of the universe is constant. Energy can neither be created nor destroyed. However, energy may be converted from one form to another.
For example, the solar panel does not destroy the solar energy; it simply converts that energy to electrical energy. Note that a fraction of that energy absorbed was lost as thermal energy. Similarly, the motor merely converts electrical energy to mechanical energy. It might also lose some thermal energy as it heats up.
Answer:
a). Determine the magnitude of the gravitational force exerted on each by the earth.
Rock:
Pebble:
(b)Calculate the magnitude of the acceleration of each object when released.
Rock:
Pebble:
Explanation:
The universal law of gravitation is defined as:
(1)
Where G is the gravitational constant, m1 and m2 are the masses of the two objects and r is the distance between them.
<em>Case for the rock </em><em>:</em>
m1 will be equal to the mass of the Earth and since the rock and the pebble are held near the surface of the Earth, then, r will be equal to the radius of the Earth .
Newton's second law can be used to know the acceleration.
(2)
<em>Case for the pebble </em><em>:</em>
The attractive force between all matter in the universe is gravity.