I been on these two question back and forth trying to figure out where to start at. Each time I think I get it I end up going way off what im suppose to do and it seem like I have trouble with doing conversion. Please help in any way to make this problem easier to solve.(adsbygoogle = window.adsbygoogle || []).push({});

In order to pass a physical education class at a university, a student must run 1.0 mi in 12.0 min. After running for 10.0 min (assume constant speed), she still has 610 yd to go. What constant acceleration does she need over the final 610 yd in order to make it?

m/s2

and

An indestructible bullet 2.00 cm long is fired straight through a board that is 10.0 cm thick. The bullet strikes the board with a speed of 400 m/s and emerges with a speed of 275 m/s. (To simplify, assume that the bullet accelerates only while the front tip is in contact with the wood.)

(a) What is the average acceleration of the bullet through the board?

m/s2

(b) What is the total time that the bullet is in contact with the board?

s

(c) What thickness of board (calculated to 0.1 cm) would it take to stop the bullet, assuming that the acceleration through all boards is the same?

cm

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# Homework Help: Acceleration of a runner

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