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I think I am doing them right but they don't match the answers that were supplied to me - i think the
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 got a = .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 got a = -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 got a = 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.
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 got a = .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 got a = -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 got a = 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.