Answer:
For the first situation, we first need to find the mass of the second train car.
In order to do that, we apply the conservation of the amount of movement:

and we have as a result:
m2 = 289.6875
For the second situation, also we will apply the conservation of the amount of movement:

and we have as a result:
V = 2.64 (it is moving to the right)
Answer:
<em>The sea bed is 1125 m deep.</em>
Explanation:
<u>Speed</u>
It's the rate of change of the distance (d) traveled by an object over time (t).
The speed can be calculated by the formula:

It's known the speed of sound in water is v=1500 m/s. A sound wave is sent to the sea bed and bounces back to the ship 1.5 seconds later.
That is the time the wave takes to travel twice the distance from the ship to the sea bed, thus the required distance uses half of that time or t=1.5/2 = 0.75 seconds.
Solving the equation for d:
d = v.t
d = 1500 m/s * 0.75 s
d = 1125 m
The sea bed is 1125 m deep.
Answer:
Balloon, leaf
Explanation:
Objects that are light and have a relatively large surface that Is affected by the friction with air.