Answer:

Explanation:
First of all, we need to find the volume of the room, which is given by

Now we can find the mass of the air by using

where
is the density of the air
is the volume of the room
Substituting,

Answer:
Rod 1 has greater initial angular acceleration; The initial angular acceleration for rod 1 is greater than for rod 2.
Explanation:
For the rod 1 the angular acceleration is
Similarly, for rod 2

Now, the moment of inertia for rod 1 is
,
and the torque acting on it is (about the center of mass)

therefore, the angular acceleration of rod 1 is


Now, for rod 2 the moment of inertia is


and the torque acting is (about the center of mass)


therefore, the angular acceleration
is


We see here that

therefore

In other words , the initial angular acceleration for rod 1 is greater than for rod 2.
Answer:
d. at the same velocity
Explanation:
I will assume the car is also travelling westward because it was stated that the helicopter was moving above the car. In that case, it depends where the observer is. If the observer is in the car, the helicopter would look like it is standing still ( because both objects have the same velocity). If the observer is on the side of the road, both objects would be travelling at the same velocity. Also recall that, velocity is a vector quantity; it is direction-aware. Velocity is the rate at which the position changes but speed is the rate at which object covers distance and it is not direction wise. Hence velocity is the best option.
Answer:
E) True. Ball B will go four times as high as ball A because it had four times the initial kinetic energ
Explanation:
To answer the final statements, let's pose the solution of the exercise
Energy is conserved
Initial
Em₀ = K
Em₀ = ½ m v²
Final
Emf = U = mg h
Em₀ = emf
½ m v² = mgh
h = v² / 2g
For ball A
h_A = v² / 2g
For ball B
h_B = (2v)² / 2g
h_B = 4 (v² / 2g) = 4 h_A
Let's review the claims
A) False. The neck acceleration is zero, it has the value of the acceleration of gravity
B) False. Ball B goes higher
C) False has 4 times the gravitational potential energy than ball A
D) False. It goes 4 times higher
E) True.