I need help with some physics questions. (Grade 11 Physics) Any help appreciated...(adsbygoogle = window.adsbygoogle || []).push({});

1. Assuming that the effective force of friction is 225N, what is the minimum work needed to push a 1.00 x 10^3kg car 45.0m up a 12.5 degree incline?

2. A 2.20kg pendelum has a period of 4.0 sec

a) What is it's frequency? (Already figured out to be 0.25)

b) What is the length of the pendelum? (Already figured out to be 3.97m)

c) What must be true about the angle (Theta) for calculated value to be correct?

d) What is the value of the restoring force when the angle (Theta) is 11.0 degrees?

e) Assuming the angle in d), what is the velocity of the pendelum bob when it passes through the equilibrium point?

f) What is the tension in the pendelum string when it passes through the equilibrium point in e)?

3. A 6200kg satellite is in a circular earth orbit that has a radius of 3.3 x 10^7m. A net external force must act on the satellite to make it change to a circular orbit that has a radius of 7.0 x 10^6. How much work must the net external force do?

Can anyone show their work and explain how they got to the answer, I realize this is very simple compared to some of the other stuff on here, but I am having trouble with physics due to a very poor professor.

Thanks

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# Homework Help: A Couple of Practice Questions

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