Question on mechanics?

Tones66

Hi. I couldn't do this question. If anyone fancies themselves could you post your solution.Any help will be appreciated. I'm stuck. Thanks.

An unplanned impact has occurred between vehicle A and a stationary vehicle B. Markings on the road indicate that after the impact B slid a distance of 2m before coming to rest. The coefficient of kinetic friction between B's tyres and the road is 0.7 and laboratory tests indicate that a coefficient of restitution e=0.4 is appropriate for this type of impact. Mass vehicle A = 1100kg. Mass vehicle B = 1300kg.

(a) Assuming that only single impact occurred, determine whether vehicle A was exceeding the relevant speed limit of 30 km/h before the impact.(15 marks)

(b) Determine the change in momentum for vehicle B. I the duration of the impact is estimated to be 0.01 s,estimate the average force exerted on B by A during impact.(5 marks)

(c)Determine the percentage of mechanical energy lost in the impact and briefly discuss possible explanations for the energy loss.(5 marks)

sceptre

Apologies to the Physics/Chem mods if you've got rules against coursework questions (follow your own rules if you do); if this is allowed, moved from UL.

You'll notice that I resisted the temptation to insert a full "two trains begin a journey, the first from NY to Philadelphia..." post along the way.

Tones66

sceptre wrote: »

Apologies to the Physics/Chem mods if you've got rules against coursework questions (follow your own rules if you do); if this is allowed, moved from UL.

You'll notice that I resisted the temptation to insert a full "two trains begin a journey, the first from NY to Philadelphia..." post along the way.

I'm sorry but i don't understand what you're after saying there?? Am I not allowed ask this question or what??

CR 7

i'm fairly sure you're not allowed ask coursework questions in the college forums, but you should read the charter to be sure.

Podge_irl

Tones66 wrote: »

I'm sorry but i don't understand what you're after saying there?? Am I not allowed ask this question or what??

You're allowed ask it here, but no one is likely to do the entire question for you. If you gave an indication of what you've done so far and where you've become stuck then we can go from there.

spideog7

Right, well it's been awhile since I did Applied Maths but I looked at that and thought "Easy!". Slow day in work so had a go at it... not as easy as I remembered A good few Googles later and a few vague recollections and I have some semblance of an answer for yea. Not sure if it's right or not but I used to be able to do these with my eyes closed not so long ago !!

A)



C)

Tones66

Thanks a million SPIDEOG that looks like a good answer. I'm rubbish at mechanics and i couldn't get my head around it at all!!

Turtwig

Podge_irl wrote: »

You're allowed ask it here, but no one is likely to do the entire question for you..

spideog7 wrote: »

Right, well it's been awhile since I did Applied Maths ...

It would seem that someone is, tut tut.

@Tone66 you'll learn alot more by working through people with the answer and learning from your mistakes than just searching for a clear solution.

spideog7

This is true but I was pretty bored and I'm not even sure if my solution is correct.

I did try to lay it out such that I explained every step I took, so hopefully the OP tries to follow the logic I used and learns from that.