Question

Classes are canceled due to snow, so you take advantage of the extra time to conduct some physics experiments. You fasten a large toy rocket to the back of a sled and take the modified sled to a large, flat, snowy field. You ignite the rocket and observe that the sled accelerates from rest in the forward direction at a rate of 15.5 m/s² for a time period of 2.90 s. After this time period, the rocket engine abruptly shuts off, and the sled subsequently undergoes a constant backward acceleration due to friction of 5.65 m/s².

After the rocket turns off, how much time does it take for the sled to come to a stop?

time: ?s

By the time the sled finally comes to a rest, how far has it traveled from its starting point?

distance traveled: ?m

Answer 1

The final velocity of sled is given by, -0+(15.5m/s - 44.9 m/s )(2.90s) The final distance of sled is given by, s-ut+-at 0+015.5 m/s') (2.90s) - 65 m The time is given by, 0+a't 44.9 m/s 5.65 m/s 7.94s Therefore, the time taken by the sled is 7.94 s The distance is given by, 65m+(44.9 m/s) (7.94 s)+-5.65m/s) (7.94 s) - 399 m Therefore, the distance of the sled is 399m