The relation between the angle of incidence and the angle of refraction is known as Snell's Law. Since the light travels with different speed in different media, the direction of the ray of light will change when it crosses the boundary between the two media
Explanation:
All the energy in oil, gas, and coal originally came from the sun captured through photosynthesis. In the same way that we burn wood to release energy that trees capture from the sun, we burn fossil fuels to release the energy that ancient plants captured from the sun.
Hi there!
Recall the following relationships:
W = Work (J)
U = Potential Energy (J)
m = mass (kg)
g = acceleration due to gravity (9.8 m/s²)
h = height (m)
t = time (s)
Begin by calculating the work:
Now, divide by the time to solve for power:
**W is the unit for power (Watts). Be careful not to get the two confused.
The efficiency of a machine indicates how well its input energy is converted to useful output energy or work. It is a major factor in the usefulness of a machine and is the fraction or percentage of the output divided by the input.
According to the Law of Conservation of Energy, the total output energy or work must equal the total input energy. However, some of the input energy does not contribute to the output work and is lost to such things as friction and heat.
Examples of machine efficiency include a lever, automobile, and perpetual motion machine.
