Answer:
A person climbs a set of stairs
Explanation:
Potential energy is said to be possessed by an object due to its position. As the height from the ground level increase, the potential energy increases. It is calculated by the below formula as :
P = mgh
Out of the given options, the option that illustrates an increase in potential energy is option (b) i.e. a person climbs a set of stairs. As he steps one stair, its position from ground increases. It means its potential energy increases.
Answer:
Decrease
Explanation:
If you crawl to the rim the rotational speed will decrease. The law of conservation of angular momentum supports this answer. And it states that :
"When the net external torque acting on a system about a given axis is. zero , the total angular momentum of the system about that axis remains constant."
Acceleration = velocity/ time
Acceleration = 0.7-0.3 /30= 0.01 m/s^2
Notice that velocity is calculated the final speed minus the initial !