The answer they are looking for is the last one. However the last two are technically correct but the third one would result in negative work.
Answer:
A
Explanation:
option A is correct
the best example of elastic collision among the following is collision between two billiard balls. In collision of two billiard balls the energy lost is very little approximately zero. hence we can say that the kinetic energy is conserved. since, the kinetic energy is conserved we can say that the collision is elastic
Answer:
These energy exchanges are not changes in kinetic energy. They are changes in bonding energy between the molecules. If heat is coming into a substance during a phase change, then this energy is used to break the bonds between the molecules of the substance. The example we will use here is ice melting into water.
Explanation:
Answer:
move upward with increasing speed
I draw fbd diagram , see in figure
when lift going upward -
F - mg = ma
f = m( a + g)
scale so highest reading
Answer:
Electric potential energy
Explanation:
The Electric potential energy of a system is less than that carried out by electrostatic forces during the development of the system (as long as charges are initially cut infinitely).
The change in potential energy between an initial and final configuration is equal to minus the work done by the electrostatic forces.
