<h3><u>Answer and explanation;</u></h3>
Reflection;
- Bounces back from an opaque material
- Bounces back from the boundary of two mediums
- Seen in mirrors
Refraction;
- Passes through a prism
- Moves from one medium to another
- Seen in lenses
Reflection refers to the bouncing of waves such as light waves. It involves a change in direction of waves when they bounce off a barrier.
Refraction is the bending of waves when they move from one medium to another. It involves a change in the direction of waves as they pass from one medium to another.
You have to move your foot to stop the car so I guess that would be considered work by moving your foot
Answer:
C. 2 mph
Explanation:
speed equals total distance covered in total time of of travel
since,
total distance = 4 miles
time taken = 2 hrs
speed = 4m / 2hrs =2mph
(a) 0.448
The gravitational potential energy of a satellite in orbit is given by:

where
G is the gravitational constant
M is the Earth's mass
m is the satellite's mass
r is the distance of the satellite from the Earth's centre, which is sum of the Earth's radius (R) and the altitude of the satellite (h):
r = R + h
We can therefore write the ratio between the potentially energy of satellite B to that of satellite A as

and so, substituting:

We find

(b) 0.448
The kinetic energy of a satellite in orbit around the Earth is given by

So, the ratio between the two kinetic energies is

Which is exactly identical to the ratio of the potential energies. Therefore, this ratio is also equal to 0.448.
(c) B
The total energy of a satellite is given by the sum of the potential energy and the kinetic energy:

For satellite A, we have

For satellite B, we have

So, satellite B has the greater total energy (since the energy is negative).
(d) 
The difference between the energy of the two satellites is:
