Homework H4.K - Fa22

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HINTS:

STEP 1 - FBD: Draw a SINGLE free body diagram (FBD) of the system of cart + cannon + cannonball.
STEP 2 - Kinetics:  Write down the impulse/momentum equation in the horizontal direction (x-direction) for the the system of cart + cannon + cannonball. Based on the above FBD, is the momentum conserved in the x-direction for that system?
STEP 3 - Kinematics
STEP 4 - Solve. Solve for the velocity of the cart + cannon.

QUESTION: The above analysis allows you to find the answer to the first part of the problem. Unfortunately, it is not useful for the find the answer to the second part of the problem where you want to find the force on the cart/cannon. What do you need to change in the analysis to find this force?

4 thoughts on “Homework H4.K - Fa22”

1. Katherine says:

For this problem, we are given mg as 60 lb, but these units don't make sense because a mass times the constant g would be in lb-ft/s^2? Or is this supposed to be lbf, which is lbft/s^2 anyway?

What final units should our horizontal force be in?

1. Clark C Addis says:

The final answer and mg should both be lbm*ft/s^2.

2. Jaime Jose Rueda says:

small question for us to analyze this problem with momentum would we need an initial velocity of the projectile before the collision?

3. Kenneth T Nakayama says:

For the initial velocity of the cart and cannon can you set them equal to zero by assuming the cannon ball is at rest in the cannon?