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Two adults and a child want to push a wheeled cart in the direction marked x in the figure (attached). The two adults push with horizontal forces F1 and F2 as shown in the figure (attached).

A) Find the magnitude of the smallest force that the child should exert. You can ignore the effects of friction.

B) Find the angle force makes with +x-direction. Take the angles positive measured counterclockwize from the +x-direction.

C) If the child exerts the minimum force found in part (A) and in part (B) , the cart accelerates at 2.0 m/s^2 in the +x - direction. What is the weight of the cart?

A) I was able to do this one fine by finding the x and y components of both forces and then finding the difference between the y components. No issue there.

B) I am completely at a loss as to what exactly they want. Is it just me or is this question poorly worded, or is that just on purpose? Anyway this is where I need a hand. I've tried using the answer I found for A (a third y force, that of the child if you will) and taking the arctan of it/the total force in x. No luck there. I've tried subtracting the arctan(force of the child/Force 2 in x) from arctan(force of the child/Force 1 in x). No luck there. I've also tried adding both of the previous angles together, and still no luck.

Can anyone offer any insight into how to approach this? I'd really appreciate it.

As far as C is concerned I am fairly certain that once I get B I'll be able to figure it out, so that can wait... for now at least. :P

EDIT: Forgot to attach the figure. Oops!

A) Find the magnitude of the smallest force that the child should exert. You can ignore the effects of friction.

B) Find the angle force makes with +x-direction. Take the angles positive measured counterclockwize from the +x-direction.

C) If the child exerts the minimum force found in part (A) and in part (B) , the cart accelerates at 2.0 m/s^2 in the +x - direction. What is the weight of the cart?

A) I was able to do this one fine by finding the x and y components of both forces and then finding the difference between the y components. No issue there.

B) I am completely at a loss as to what exactly they want. Is it just me or is this question poorly worded, or is that just on purpose? Anyway this is where I need a hand. I've tried using the answer I found for A (a third y force, that of the child if you will) and taking the arctan of it/the total force in x. No luck there. I've tried subtracting the arctan(force of the child/Force 2 in x) from arctan(force of the child/Force 1 in x). No luck there. I've also tried adding both of the previous angles together, and still no luck.

Can anyone offer any insight into how to approach this? I'd really appreciate it.

As far as C is concerned I am fairly certain that once I get B I'll be able to figure it out, so that can wait... for now at least. :P

EDIT: Forgot to attach the figure. Oops!