Answer:
Fc = 89.67N
Explanation:
Since the rope is unstretchable, the total length will always be 34m.
From the attached diagram, you can see that we can calculate the new separation distance from the tree and the stucked car H as follows:
L1+L2=34m
Replacing this value in the previous equation:
Solving for H:

We can now, calculate the angle between L1 and the 2m segment:

If we make a sum of forces in the midpoint of the rope we get:
where T is the tension on the rope and F is the exerted force of 87N.
Solving for T, we get the tension on the rope which is equal to the force exerted on the car:

A
More concentrated means more collisions per unit volume, and as the volume stays the same and only concentration changes, the there are more collisions
Answer:
In 0.5 seconds.
Explanation:
The time would be the same because it only depends on the height and the vertical component of the initial velocity. This is of course because each direction must be treated independently. Since between both cases only the horizontal speed changes, the height is the same and the vertical component of the initial velocity is null for both, the time to fall is the same.
Answer:
D. Allowing free electrons to escape from a negatively charged body
Explanation:
In order to neutralize a charge, an equal and opposite charge must be added or brought in contact with it.
From the options provided, only D is wrong.
Allowing free electrons to escape from a negatively charged body will cause the body to be positively charged. In such a body, the number of positively charged particles will be more. A neutralized atom or neutral atom has equal amount of positive and negative charges.