Answer:
you want to know newtons first law here.
Explanation:
An object that is at rest stays at rest or stays in motion.
Answer:
The system's potential energy is -147 J.
Explanation:
Given that,
Energy = 147 J
We know that,
System is isolated and it is free from external forces.
So, the work done by the external forces on the system should be equal to zero.

We need to calculate the system's potential energy
Using thermodynamics first equation

Put the value into the formula


Hence, The system's potential energy is -147 J.
Answer:

Explanation:
Given that,
The mass of a golf ball, m = 40 g = 0.04 kg
Its angular velocity, 
The radius of the sphere is 2.5 cm or 0.025 m
We need to find the magnitude of the angular momentum of the ball. It is given by the formula as follows:

Where I is moment of inertia
For sphere, 

So, the magnitude of the angular momentum of the sphere is
.