Answer: Friction also prevents an object from starting to move, such as a shoe placed on a ramp. When friction acts between two surfaces that are moving over each other, some kinetic energy is transformed into heat energy. Friction can sometimes be useful.
Explanation:
Answer:
P = 227 N
Explanation:
Assuming the crate is on horizontal ground and subject to a horizontal force.
F = ma
P - μmg = ma
P = m(a + μg)
P = m(v²/2s + μg)
P = 50(4²/(2(5))+ 0.3(9.8))
P = 227 N
Answer:
Final velocity of the car will be -9.28 m/sec
Explanation:
We have given that the car starts from the rest so initial velocity of the car u = 0 m /sec
Acceleration of the car 
in negative direction so acceleration will be 
From first equation of motion we know that
v = u+at
So 
So final velocity will be -9.28 m/sec
