Question

a bobsled has a momentum of 3000 kg·m/s to the east. after the rider gives it a push, its momentum increases to 5500 kg·m/s to the east. what impulse is applied to the bobsled?

a. 8500 kg·m/s west
b. 2500 kg·m/s east
c. 2500 kg·m/s west
d. 8500 kg·m/s east

Explanation:

Step1: Recall impulse - momentum theorem

Impulse $J=\Delta p$, where $\Delta p$ is the change in momentum.

Step2: Identify initial and final momentum

Initial momentum $p_i = 3000\ kg\cdot m/s$ (east), final momentum $p_f=5500\ kg\cdot m/s$ (east).

Step3: Calculate change in momentum

$\Delta p=p_f - p_i=5500\ kg\cdot m/s- 3000\ kg\cdot m/s = 2500\ kg\cdot m/s$. Since the final momentum is greater and both are in the east - direction, the impulse is in the east - direction.

Answer:

B. $2500\ kg\cdot m/s$ east