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Physics exam question

So I've got this question for revision that is similar to my exam. I can't seem to figure it out, can anyone help me? It's a question regarding a Gravitron.

Information I'm given:

Mass block = 216.92kg
Cable hub radius = 2 metres
Time = 10 seconds
Torque = 4070 kg/m/s^2
Tension of cable = 2035 Newtons
Gravitational Force = 9.8m/s^2

Question: Calculate the distance the mass block falls.

[url=http://i54.tinypic.com/ejvdqb.jpg]Here's the question scanned[/url]

May 31, 2011

7 Comments • Newest first

clintyip

@Skrato: No I didn't O_O, that actually looks right. Time to spam my teacher's inbox. THANKS!

Reply May 31, 2011
Skrato

Did you take tension into account?

Net force = 2127.9852 - 2035 = 92.9852 N

A = F/m = 0.42866125760649087221095334685598 ms-2

s = 0.5at^2 = 21.4m

Reply May 31, 2011
clintyip

@Skrato: I actually did do that, and I came out with 469 metres. That doesn't seem right

Reply May 31, 2011
Skrato

I didn't study torque for my IB physics, but I believe we need to know the maximum speed.

Actually can't you just use suvat? a = F/m, you know u,a,t,and find s using s=ut+0.5at^2

Reply May 31, 2011 - edited
clintyip

Hold up, I'll upload the sheet of paper as an image.

EDIT: [url=http://i54.tinypic.com/ejvdqb.jpg]Here[/url]

Reply May 31, 2011 - edited
clintyip

@Skrato: It's a Gravitron, meaning a ferris wheel sorta thing. I'll type out the section of the question:

"So that a smaller motor can be used to drive the ride, it is proposed to accelerate the Graitron to its maximum speed by using a falling mass attached to a cable wound round hub of radius 2 metres. It is proposed this mass would fall a distance, then be raised by the motor at a slower rate during downtime"

The first question says calculate the mass necessary to acclerate the Gravitron to max speed in 10 seconds, which I calculated to be 216.92kg (from original thread post)

Then the second part of the question says calculate the distance the mass falls.

Reply May 31, 2011 - edited
Skrato

Unfortunately, I don't know how everything is connected. You need to explain the situation.

Reply May 31, 2011 - edited