I am currently stuck on two problems:(adsbygoogle = window.adsbygoogle || []).push({});

#1 A bat hits a moving baseball. If the bat delivers a net eastward impulse of 0.9 N-s and the ball starts with an initial horizontal velocity of 3.8 m/s to the west and leaves with a 5.3 m/s velocity to the east, what is the mass of the ball (in grams)?

I set J=deltaP

.9=95.3+3.8)m

m=.9/(5.3+3.8).

#The second problem has a force vs. time for an impulsive force graph and asks: The force shown in the figure below is the net eastward force acting on a ball. The force starts rising at t=0.012 s, falls back to zero at t=0.062 s, and reaches a maximum force of 35 N at the peak. Determine with an error no bigger than 25% (high or low) the magnitude of the impulse (in N-s) delivered to the ball. Hint: Do not use J = FΔt. Look at the figure. Find the area of a nearly equally sized triangle.

I am sure tthis problem is very simple but do not have a confident approach for some reason, I presume I find the time when it peaks at 35 N(.062-.012) and use this as my base? Then I would apply A=.5(35)(.062-.012)?

Any help would be greatly appreciated.

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# Homework Help: Impulse/Momentum problems

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