I believe it is called centripetal force <span />
The type of radiation that can penetrate through paper, but not through wood is called beta rays. Beta rays can penetrate paper and air, but a thin piece of alimony can stop it. Gamma can cut through anything except lead and many inches of concrete. Alpha can be stopped by paper and not penetrated. The correct answer is B.
The answer is (a) because movement is acceleration
A generator converts mechanical energy into electrical energy, while a motor does the opposite - it converts electrical energy into mechanical energy