Answer:
d- Earth revolves around the sun.
Explanation:
Earth rotation can be defined as the amount of time taken by planet earth to complete its spinning movement on its axis.
This ultimately implies that, the rotation of earth refers to the time taken by earth to rotate once on its axis. One spinning movement of the earth on its axis takes approximately 24 hours to complete with respect to the sun.
On the other hand, earth revolution can be defined as a complete trip along a path around the sun. This path is known as an orbit and it typically takes the Earth 365¼ days to complete it's journey around the Sun.
When a constellation (stars) changes its position in the sky, at the same time of the evening and over a period of several weeks; it ultimately implies or is an evidence that Earth revolves around the sun.
Answer:
K/2
Explanation:
The law of conservation of mechanical energy states that the sum of the kinetic and potential energies is a constant at any point.
At maximum height, the glove has purely potential energy but at the bottom, it has purely kinetic energy.
The potential energy at the top = kinetic energy at the bottom. The potential energy is given by

At half height, this potential energy is

At this height, PE + KE = Constant = KE at bottom or PE at maximum height.


Answer:
c)
Explanation:
A collision is said to be elastic when the total kinetic energy is the same after the collision. The speed of objects that are stuck together will always be less than the initial speed of the object that was in motion given that the other particle was at rest. It is because the kinetic energy of the system was due to the moving object. The objects have a greater overall mass when they are stuck. If the kinetic energy is the same and the mass increases, the velocity must decrease.