Answer: C
Reflection
Explanation: Light travels in a straight line. Reflection is one of the properties of light. And this is the property in which mirror make use of. The ability of light to bounce back. It's this bouncing back characteristics of light ray that eventually produce the image of an object by the mirror.
If the light ray is absorbed, no image will be produced.
Answer:
Explanation:
Given
mass of crane 
distance moved 
Since it is moving with a constant velocity therefore net force on it is zero
Tension force=weight
T=mg
Work done by Tension T is



Work done by Gravity will be equal in magnitude but opposite in sign and can be obtained by work energy theorem which states that change in kinetic energy of object is equal to work done by all the forces


Answer:

Explanation:
Let the charge on the ball bearing is q.
charge on glass bead, Q = 20 nC = 20 x 10^-9 C
Force between them, F = 0.018 N
Distance between them, d = 1 cm = 0.01 m
By use of Coulomb's law in electrostatics

By substituting the values


Thus, the charge on the ball bearing is 
By definition, the law of conservation of energy states that:
Ei = Ef
Where,
Ei: initial energy
Ef: final energy
Therefore, no matter the type of energy, always the final energy is equal to the final energy.
Energy can be transformed into another type of energy. For example, the potential energy can be transformed into kinetic energy.
Also, energy is not created, nor destroyed.
Answer:
The following is not true about the Law of Conservation of Energy:
A. It states that the total energy in the universe keeps increasing.