I need some help with these two problems:(adsbygoogle = window.adsbygoogle || []).push({});

1. A wheel of radius 30 cm has forces applied to it as shown in the figure below. Find the torque produced by the force of (a) 4 N (b) 9 N (c) 7 N (d) 6 N. See attachment for figure.

(a) = _____1.2 N*m_____ counterclockwise?

(b) = _____2.7 N*m_____ clockwise?

(c) = __________ N*m

(d) = __________ N*m clockwise

For a, I did: (4N)(.3 M ) = 1.2 N*m

for b, (9 N)(.3 M) = 2.7 N*m

for c, I don't know how to solve it if hte force isn't perpendicular.

for d, same as c. Does anybody know how to solve for c and d, and does anybody know if a and b are correct?

2. A wheel, of mass 6 Kg and radius of gyration 40 cm, is rotating at 300 rpm. Find its momentum of inertia and its rotational KE.

I got:

I = mr^2 = (6 Kg)(0.4 m)^2 = 0.96 kg*m^2. Is that right???

And I'm not sure how to find the rotational kinetic energy. Is there an equation I need?

All help is appreciated. thank you

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# Homework Help: Homework Help, Please

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