- #1

WoodenFire

- 2

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Here is the actual physics problem. Below it I will try to explain exactly how I thought to figure it out. I would appreciate it if you corrected me If I made any errors. I am very sketchy on this one after being out for a week from class.

http://img74.imageshack.us/img74/2937/img012brz6.th.jpg

For some reason the picture isn't showing to most people... here is the imageshack direct link. http://img74.imageshack.us/my.php?image=img012brz6.jpg

**Note : the friction value is for the stretch of 9.6m in the picture.

u = .89, u = (Ff/Fn), 1714kg + 750kg = (2464kg)(9.8m/s/s) = 24147.2N, .89 = (Ff)/(24147.2), Ff = 21491N

F = ma, 21491 = 2464a, a = 8.71m/s/s

d = (1/2)(a)(t^2), 9.6m = 4.36(t^2), t = 1.48s

P = Momentum, (P)/(Ff) = t **I made this equation up because of the fact that momentum is Newtons x Seconds and dividing it by Newtons will give me time., (P)/(21491)=(1.48), P = 31806.7NS

Plugging into a triangle the 31806.7NS as the hypotinuse and 48.8degrees as the angle, I used cosine and sine to get the following information.

1) North = 20950.7NS

2) East = 23931.8NS

P = (M)(V)

Car : 20950.7 = (750)(V), V = 27.9m/s ~ 56mph

Truck : 23931.8 = (1714)(V), V = 13.96m/s ~ 28mph

My conclusion is that the car obviously didn't stop at the stopsign and was speeding while the truck kept just under the speed limit. The blame would entirely be on the driver of the car.

Due tomarrow!

http://img74.imageshack.us/img74/2937/img012brz6.th.jpg

For some reason the picture isn't showing to most people... here is the imageshack direct link. http://img74.imageshack.us/my.php?image=img012brz6.jpg

**Note : the friction value is for the stretch of 9.6m in the picture.

u = .89, u = (Ff/Fn), 1714kg + 750kg = (2464kg)(9.8m/s/s) = 24147.2N, .89 = (Ff)/(24147.2), Ff = 21491N

F = ma, 21491 = 2464a, a = 8.71m/s/s

d = (1/2)(a)(t^2), 9.6m = 4.36(t^2), t = 1.48s

P = Momentum, (P)/(Ff) = t **I made this equation up because of the fact that momentum is Newtons x Seconds and dividing it by Newtons will give me time., (P)/(21491)=(1.48), P = 31806.7NS

Plugging into a triangle the 31806.7NS as the hypotinuse and 48.8degrees as the angle, I used cosine and sine to get the following information.

1) North = 20950.7NS

2) East = 23931.8NS

P = (M)(V)

Car : 20950.7 = (750)(V), V = 27.9m/s ~ 56mph

Truck : 23931.8 = (1714)(V), V = 13.96m/s ~ 28mph

My conclusion is that the car obviously didn't stop at the stopsign and was speeding while the truck kept just under the speed limit. The blame would entirely be on the driver of the car.

**What do you think?**Due tomarrow!

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