Answer:

(we need the mass of the astronaut A)
Explanation:
We can solve this by using the conservation law of the linear momentum P. First we need to represent every mass as a particle. Also we can simplify this system of particles by considering only the astronaut A with an initial speed
of 0 m/s and a mass
and the IMAX camera with an initial speed
of 7.5 m/s and a mass
of 15.0 kg.
The law of conservation says that the linear momentum P (the sum of the products between all masses and its speeds) is constant in time. The equation for this is:

By the law of conservation we know that
For
(final linear momentum) we need to treat the collision as a plastic one (the two particles stick together after the encounter).
So:


Answer:
25.82 m/s
Explanation:
We are given;
Force exerted by baseball player; F = 100 N
Distance covered by ball; d = 0.5 m
Mass of ball; m = 0.15 kg
Now, to get the velocity at which the ball leaves his hand, we will equate the work done to the kinetic energy.
We should note that work done is a measure of the energy exerted by the baseball player.
Thus;
F × d = ½mv²
100 × 0.5 = ½ × 0.15 × v²
v² = (2 × 100 × 0.5)/0.15
v² = 666.67
v = √666.67
v = 25.82 m/s
Answer:
Two equal and opposite parallel forces not acting along the same line, form a couple. A couple is always needed to produce the rotation.
For example, turning a key in a lock and turning a steering wheel.
Answer:
The moun lives 2.198*10^-6 s as measured by its own frame of reference
The Earth moved 648 m as measured by the moun's frame of reference
Explanation:
From the point of view of the observer on Earth the muon traveled 3.53 km at 0.983c
0.983 * 3*10^8 = 2.949*10^8 m/s
Δt = d/v = 3530 / 2.949*10^8 = 1.197*10^-5 s
The muon lived 1.197*10^-5 s from the point of view of the observer.
The equation for time dilation is:

Then:

From the point of view of the moun Earth moved at 0.983c (2.949*10^8 m/s) during a time of 2.198*10^-6, so it moved
d = v*t = 2.949*10^8 * 2.198*10^-6 = 648 m