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suspenc3
Oct30-05, 04:40 PM
An old streetcar rounds a flat corner of radius = 9.1m at 4.444 m/s.
What angle with the vertical will be made by the loosely hanging hand straps.

I dont really know what I am looking for, Can anyone Help?

Päällikkö
Oct30-05, 05:01 PM
Start by drawing a diagram. What forces are acting on the hand straps? Think why the hand straps should form any angle with the vertical.

suspenc3
Oct30-05, 05:13 PM
centripetal acceleration would act on the handstraps
a = vsquared/r

a=2.1m/s(squared)

is that all that acts on them

Päällikkö
Oct30-05, 05:15 PM
Almost. What keeps the car (and the hand straps, and pretty much everything else) on ground? :smile:

suspenc3
Oct30-05, 05:18 PM
Gravity ?

Päällikkö
Oct30-05, 05:20 PM
Yep.
Now, the direction of the resultant force?

suspenc3
Oct30-05, 05:24 PM
could i do this:

tan(theta) = 9.8m/s(squared) / 2.1m/s(squared

Päällikkö
Oct30-05, 05:27 PM
Yes, but as the requested angle was the angle with the vertical (not horizontal), you should switch the forces' (accelerations', as mass cancels out) places.

suspenc3
Oct30-05, 05:30 PM
ohhh..oops..thats what i meant in the first place

Thanks