Answer:
The minimum distance in which the car will stop is
x=167.38m
Explanation:

∑F=m*a
∑F=u*m*g
The force of friction is the same value but in different direction of the force moving the car so it can stop so



Answer:
The value is 
Explanation:
From the question we are told that
The magnitude of the horizontal force is 
The mass of the crate is 
The acceleration of the crate is 
Generally the net force acting on the crate is mathematically represented as

Here
is force of kinetic friction (in N) acting on the crate
So

=> 
You can use mostly anything as long as it is circular. Depending on how big it is, you could use sturdy paper plates and use a stick/rod and tape to hold it together, or you could use bottle caps if the car you are trying to make is really small.
Answer:
T=13.72N
Explanation:
The tension before the ball is released have no angle is in rest at the same axis of the weight so:
∑F=0
Using Newton law in this case the ball is tied so tension before become to swing is
∑F=FN-T=0



