1) The distance travelled by the rocket can be found by using the basic relationship between speed (v), time (t) and distance (S):
Rearranging the equation, we can write
In this problem, v=14000 m/s and t=150 s, so the distance travelled by the rocket is
2) We can solve the second part of the problem by using the same formula we used previously. This time, t=300 s, so we have:
Answer: 91.94 kg
Explanation: Supoose Al's mass is m. The combined mass is 168kg, so Jo's mass is 168 - m.
The Law of Conservation of Momentum states that when two objects collide, the total momentum of both objects before the collision is the same as the total momentum of both objects after the collision.
At the beginning, Al and Jo are united without movement, so their initial momentum is zero.
After the release of their hands, Al goes in one direction and Jo moves to the opposite direction. Suppose the direction Al is moving is positive. Conservation of momentum will be
where
index i referes to initial momentum
index f to final momentum
index 1 refers to Al
index 2 to Jo
Calculating:
m = 91.94
Al has a mass of 91.94 kg.