Answer:
0.47 N
Explanation:
Here we have a ball in motion along a circular track.
For an object in circular motion, there is a force that "pulls" the object towards the centre of the circle, and this force is responsible for keeping the object in circular motion.
This force is called centripetal force, and its magnitude is given by:

where
m is the mass of the object
is the angular velocity
r is the radius of the circle
For the ball in this problem we have:
m = 40 g = 0.04 kg is the mass of the ball
is the angular velocity
r = 30 cm = 0.30 m is the radius of the circle
Substituting, we find the force:

Answer:
The coefficient of rolling friction will be "0.011".
Explanation:
The given values are:
Initial speed,

then,


Distance,
s = 18.2 m
The acceleration of a bicycle will be:
⇒ 
On substituting the given values, we get
⇒ 
⇒ 
⇒ 
⇒ 
As we know,
⇒ 
and,
⇒ 
⇒ 
On substituting the values, we get
⇒ 
⇒ 
Answer:
Height above a surface
Explanation:
Gravitational potential energy is the energy which an object possesses due to its position above a surface.
It is also the amount of work a force has to do in order to bring an object from a particular position to a point of reference.
It is given mathematically as:
P. E. = m*g*h
where m = mass of the body
g = acceleration due to gravity
h = height above a surface
m*g represents the weight of the object.
Hence, Gravitational potential energy is the product of an object's weight and its height above a surface/reference point.