Mechanical advantage of a machine is the ratio of the output force over the input force or M=Fo/Fi. Since M=1, Fi=Fo, or the input force is equal to the output force. This means that to raise the refrigerator that weighs 900 N, we need the same input force of 900 N, or Fo=Fi=900 N.
The answer is D. Either absorbed or reflected. The reason is because if no light is being shown on the other side, the substance is not letting any light pass through. Since we do not know anything else about the substance, we do not know which one of the two it is doing. The scientist would not see any light on the detector if 100% of the light is reflected and the same thing would happen if 100% of the light was absorbed.
Hello!
Recall the equation for gravitational force:

Fg = Force of gravity (N)
G = Gravitational constant
m1, m2 = masses of objects (kg)
r = distance between the objects' center of masses (m)
There is a DIRECT relationship between mass and gravitational force.
We are given:

If we were to double one mass and triple another, according to the equation:

Thus:
