If net external force acting on the system is zero, momentum is conserved. That means, initial and final momentum are same → total momentum of the system is zero.
This next statement is a big deal. It should be up on a board, surrounded
by flashing red and yellow lights, and hung on the wall of every Science
classroom. Although we never see it in our daily lives, it's fundamental to
the workings of the universe, and it's also Newton's first law of motion:
<em>Without friction, it doesn't take <u>ANY</u> force to keep a moving object
moving. </em><em>Force is only required to <u>change</u> the object's speed, or to
<u>change</u> the direction </em><em>in which it's moving.</em>
The answer to the question is: On a level road, and neglecting any friction,
the engine doesn't have to supply ANY force to keep the car going at the
same speed.
Answer:
The value is 
Explanation:
From the question we are told that
The speed of in a vacuum is 
The speed of light in the material is 
Generally the reflection of the material is mathematically represented as
=> 
=>
It is hammer because hammers are not examples of a simple machine
<u>Answer </u>
A. that the initial gravitational potential energy of the masses transformed into kinetic energy of the paddles and then to thermal energy in the water
<u>Explanation</u>
James Joule allowed some water to fall from a height of 1 foot. the water would turn a paddle wheel at the bottom causing a temperature of water to raise.
The height form which the water fell, mass and the temperature of water was measured and used to calculate mechanical equivalent of heat.
From the choices given the best answer is A. that the initial gravitational potential energy of the masses transformed into kinetic energy of the paddles and then to thermal energy in the water.
