Answer:
a) KE = 888.26J
b) N = 294.5 turns
Explanation:
For the kinetic energy:
The inertia is:
So, the kinetic energy will be:
Now, friction force is:
Ff = μ*N = 0.80*5N = 4N
The energy balance would be:
Kf - Ko = Wf where Kf=0; Ko = 888.26J; and Wf is the work done by friction force.
Wf = -Ff*d = -Ff*N*2*π*R where N is the amount of turns it gives.
Replacing these values into the energy balance:
0-888.26=-4*N*2*π*0.12
-888.26=-0.96*π*N
N=294.5 turns
We need to find the average speed of the ball during the motion of 1 m
In order to find that we took several reading and found following times to cover the distance of 1 m
t1 = 2.26 s
t2 = 2.38 s
t3 = 3.02 s
t4 = 2.26 s
t5 = 2.31 s
Now in order to find the average time we can write
So average time to cover the distance of 1 m by ball will be 2.45 s
here 3.02 s is not the average time but we can say it is the median of the readings of all possible values which we can not use in our calculation as average time