# Homework H3.G - Fa22

Any questions??

## 8 thoughts on “Homework H3.G - Fa22”

1. Quqi Zhang says:

If we want to relate vc to vo first, then, vb to vc. how we can find the distance between point C and point O in x direction.

1. If you just use x as a variable in the vector for r(c/o) then x will no longer be considered when you do the cross product since omega O is in the J direction. I think.

2. Noah says:

Does anyone else sometimes decide to isolate for the velocity and acceleration of a single segment of a dependent/relative system in order to try to understand how its moving before trying to relate that the the observer? I feel like it helps me conceptually understand better, but it takes longer.

3. Katherine says:

When it asks for the angular velocity of the disk, that means omega total at the disk right? Because it gives us a value called omega disk and thats kinda confusing...

1. CMK says:

You are correct. The nomenclature here is not very clear. You are asked to find the total angular velocity of the disk. omega_disk is a component of the angular velocity of the disk relative to the arm.

4. Cameron Greeson says:

In part b, the omega in the equation used to solve for the acceleration of Ac is not the same that we found in part a, correct?

1. CMK says:

Consider that point C moves on a circular path of radius "b" with a constant speed of b*omega_0. Use that to determine the acceleration vector for point C.

5. skfree says:

I think there might be a mistake in the solution video around 10:30. You say k x i is -j, making the sign of r*w_d^2 positive, but isn't k x i equal to j, keeping the term negative?