Answer:
(E) none of these.
Explanation:
first that all we need the meaning of a Watt
<em>" is a unit of power. In the International System of Units (SI) it is defined as a derived unit of 1 </em><em>joule</em><em> per </em><em>second</em><em>,[1] and is used to quantify the rate of </em><em>energy</em><em> transfer." </em>
<em>definition taken from wikipedia.org</em>
now with this concept we have that:
100 W means 100 J/s .Therefore it uses 100 J energy per second
therefore on the answers don't mention this three terms together
Joules, energy and second so the answer must be.
(E) None of these
Answer:
D. Because mass and energy are both conserved, the total amounts of mass and energy are the same before and after impact.
Explanation:
As we know that, the energy in motion is Kinetic Energy mathematically given as:
<u>Now, according to the law of conservation of energy:</u>
where:
mass of racquet and ball respectively and 
are their respective initial velocities.
are the respective final velocities.
<u>Also the law of conservation of momentum is applicable in this case:</u>
In this case the velocity of the lighter mass will get increases in the final condition.
Answer:
Thermal energy.
Explanation:
We know that energy is conserved and it only transform one form to another form ,Like potential energy transform in to kinetic energy when a ball fall down from a height and obtain some velocity.
In this case energy changes from gravitational energy to kinetic energy then elastic energy and after some time this energy will convert in to thermal energy.
So the answer is thermal energy.
