Answer:

Explanation:
As we know that the acceleration of a point on the rim of the disc is in two directions
1) tangential acceleration which is given as

2) Centripetal acceleration

here we know that


now we know that net linear acceleration is given as

so we have


Answer:
0.4
Explanation:
F-Fr=ma where F is applied force, Fr is friction, m is mass and a is acceleration.
Since the mass is moving with a constant velocity, there's no acceleration hence
where N is the weight of object and \mu is coefficient of kinetic friction.
the subject

Substituting F for 8 N and N for 20 N

Therefore, coefficient of kinetic friction is 0.4
Step 1: list known info
distance(change in position (Δx))= 18m+22m= 40m
time= 20 seconds
Step 2 :solve for velocity
velocity= Δx÷time
v= 40/20= 2m/s
Answer: the velocity is 2 meters per a second (m/s)