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I kno this is pretty simple and the answer is probably staring me in the face, but i'm lost for some reason. Our teacher gave back our tests so i have the answer, but I'm not sure how to get it. I havent had a chance to speak to my teacher yet, but i intend to tomorrow if no one helps me first.

A bowling ball [(mass = 7 kg)(radius = .50m)] rolls without slipping down a 3m high ramp. Starting from rest, find the velocity at the bottom of the ramp.

Bowling ball inertia = I = (2/5)(M)(R)^2 = (0.7)

I used conservation of angular momentum

(1/2)(I-initial)(omega-initial)[itex]^{2}[/itex] + mg(h-initial) = (1/2)(I-final)(omega-final)[itex]^{2}[/itex] + mg(h-final)

after calculating i got omega-final = 24 (actually 24.25, but he instructed us to round to the nearest whole number)

i converted that to v = 12

which is wrong

i was supposed to set it up as:

(1/2)(I-initial)(omega-initial)[itex]^{2}[/itex] + mg(h-initial) = (1/2)(I-final)(omega-final)[itex]^{2}[/itex] + mg(h-final) + (1/2)m(v)[itex]^{2}[/itex]

and v = 6.5 is the answer

i was under the impression we were supposed to find the angular velocity at the bottom of the ramp and convert to linear velocity

i'm not sure how he got v = 6.5

## Homework Statement

A bowling ball [(mass = 7 kg)(radius = .50m)] rolls without slipping down a 3m high ramp. Starting from rest, find the velocity at the bottom of the ramp.

## Homework Equations

Bowling ball inertia = I = (2/5)(M)(R)^2 = (0.7)

## The Attempt at a Solution

I used conservation of angular momentum

(1/2)(I-initial)(omega-initial)[itex]^{2}[/itex] + mg(h-initial) = (1/2)(I-final)(omega-final)[itex]^{2}[/itex] + mg(h-final)

after calculating i got omega-final = 24 (actually 24.25, but he instructed us to round to the nearest whole number)

i converted that to v = 12

which is wrong

i was supposed to set it up as:

(1/2)(I-initial)(omega-initial)[itex]^{2}[/itex] + mg(h-initial) = (1/2)(I-final)(omega-final)[itex]^{2}[/itex] + mg(h-final) + (1/2)m(v)[itex]^{2}[/itex]

and v = 6.5 is the answer

i was under the impression we were supposed to find the angular velocity at the bottom of the ramp and convert to linear velocity

i'm not sure how he got v = 6.5

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