Answer:
82.4 cm
Explanation:
∑F = ma
kx cos θ = ma
x = ma / (k cos θ)
x = (10 kg) (5 m/s²) / (70 N/m cos 30.0°)
x = 0.824 m
x = 82.4 cm
Twice the amplitude of each wave
Answer:

Explanation:
First, we write the equations of motion for each axis. Since the crate is sliding with constant speed, its acceleration is zero. Then, we have:

Where T is the tension in the rope, F is the force exerted by the first worker, f_k is the frictional force, N is the normal force and mg is the weight of the crate.
Since
and
, we can rewrite the first equation as:

Now, we solve for
and calculate it:

This means that the crate's coefficient of kinetic friction on the floor is 0.18.