<h3>Answer: </h3>
(a)
<h3>Explanation </h3>
- Newtons First Law can be written as the formula

since acceleration is the changing of velocity as its formula is

Thus, a force must be acting on an accelerating/decelerating object
- It is not mass as the mass does not act on the object but rather the mass is acting on the surface of the ground.
- Changing velocity is already acceleration
- inertia is the term used to describe Newtons first law
Answer:
The angular speed of the sphere at the bottom of the hill is 31.39 rad/s.
Explanation:
It is given that,
Weight of the sphere, W = 240 N
Radius of the sphere, r = 0.2 m
Angle with the horizontal, 
We need to find the angular speed of the sphere at the bottom of the hill if it starts from rest.
As per the law of conservation of energy, the total energy at the top is equal to the energy at the bottom.
Gravitational energy = translational energy + rotational energy
So,

I is the moment of inertia of the sphere, 
Also, 
h is the height of the ramp, 

On solving the above equation we get :



So, the angular speed of the sphere at the bottom of the hill is 31.39 rad/s. Hence, this is the required solution.
At standard atmospheric pressure, 100° C
is defined as the boiling point of water.