Answer:
D
Explanation:
When the spring is wound, then it gathers potential energy in the form of tension energy. As it slowly unwinds, the potential energy is converted to kinetic energy of the hands' movements of the clock. This energy is channeled through the use of cogs/gears in the clock.
Answer:
Light travels as a wave. But unlike sound waves or water waves, it does not need any matter or material to carry its energy along. This means that light can travel through a vacuum—a completely airless space. (Sound, on the other hand, must travel through a solid, a liquid, or a gas.)
Explanation:
Answer: Descartes was more of speed which defers from modern day velocity.
Explanation:
Descartes law if conservation referred or defined “motion” rather than “momentum” as what is obtainable in today's world as ”speed” the rate at which something moves rather than “velocity” which is a product of speed and direction. So in conclusion Descartes was more of speed which defers from modern day velocity.
Answer:
Force, F = 187.42 N
Explanation:
It is given that,
Mass of boy, m = 30 kg
Acceleration due to gravity, 
Radius of curvature of the roller coaster, r = 15 m
Speed of the car, v = 7.3 m/s
The force acting on the boy are force of gravity and the centripetal force. The net force acting on him is as follows :



F = 187.42 N
So, he press against the seat with a force is 187.42 N. Hence, this is the required solution.
Newtons third law of motion states that for every action, there is an equal an opposite reaction. This means that the force on back on something is going to be equal in size and opposite in direction.