I think im doing them right but they dont match the answers that were supplied to me - i think the(adsbygoogle = window.adsbygoogle || []).push({});

answers may have typos.

1. A bike accelerates uniformly from rest to a speed of 7.10 m/s over a distance of 35.4 m.

Determine the acceleration of the bike.

my answer: I used the formula v^2 = vo^2 + 2ad and gota = .712 m/s^2

2. A car traveling at 22.4 m/s skids to a stop in 2.55 s. Determine the skidding distance of the

car (assume uniform acceleration).

my answer: I solved for acceleration first (-8.78 m/s^2) then used d=Vot + 1/2(a)t^2 to get

d = 28.57 m.

3. A bullet is moving at a speed of 367 m/s when it embeds into a lump of moist clay. The bullet

penetrates for a distance of 0.0621 m. Determine the deceleration of the bullet when moving into

the clay.

my answer: I used the formula v^2 = vo^2 + 2ad and gota = -1.08 x 10^6 m/s. (my issue

here is that the answer should be negative, not positive. right?)

4. A dragster accelerates to a speed of 112 m/s over a distance of 398 m. Determine the

acceleration of the dragster.

my answer: Once again I used the formula v^2 = vo^2 + 2ad (with Vo = 0; at least I assume

that is true) and gota = 15.76 m/s^2.

I think my equations and answers are right but if not, can someone help me out and correct me where I have made mistakes.

Thanks.

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# Homework Help: Can someone check my answers on these kinematics questions?

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