Answer:
Explanation:
Magnitude of frictional force = μ mg
μ is either static or kinetic friction.
To start the crate moving , static friction is calculated .
a ) To start crate moving , force required = μ mg where μ is coefficient of static friction .
force required =.517 x 56.6 x 9.8 = 286.76 N .
b ) to slide the crate across the dock at a constant speed , force required
= μ mg where μ is coefficient of kinetic friction , where μ is kinetic friction
= .26 x 56.6 x 9.8 = 144.21 N .
Answer: 
Explanation:
Given
Distance putty has to travel is 3.5 m
The initial speed of putty is 9.50 m/s
Using equation of motion to determine the velocity of putty just before it hits ceiling


So, the velocity of putty just before hitting is 
Answer:
0.72
Explanation:
= Time period of oscillation = 1.5 s
Angular frequency is given as

= Amplitude of oscillation = 40 cm = 0.40 m
= Coefficient of static friction = ?
= acceleration of the block
= mass of the block
Maximum acceleration of the block is given as

frictional force is given as

As per newton's second law

Answer:
distance/ kinetic
Explanation:
According to the work energy theorem, the work done by all forces is equal to the change in kinetic energy of the body.
So, As the force is applied in the same direction of the distance traveled,so only the kinetic energy of the body changes as after application of force, the speed of the body changes.