Answer:
The momentum would be doubled
Explanation:
The magnitude of the momentum of the freight train is given by:
where
m is the mass of the train
v is its speed
In this problem, we have that the speed of the train is unchanged, while the mass of the train is doubled:
therefore, the new momentum is
so, the momentum has also doubled.
Answer:
D. Drawing a conclusion about something
Work = (force) x (distance) =
(200 N) x (3.5 m) = <em>700 joules</em>
Answer:
60 boxes
Explanation:
The work done by lifting a single box is equal to the force applied (the weight of the box) times the displacement of the box:
Power is related to the work done by the equation:
where W is the work done and t is the time. In this problem, we are told that the power used is P=60.0 W, while the time taken is t = 1 min = 60 s, so the total work done must be
Therefore, the number of boxes that she has to lift in order to use this power is the total work divided by the work done in lifting each box:
<span>(300 m/s)/(10 r/s) = 30 m/round.</span>