Solving Two-Horse Stump Pulling Problem: Find F2

[Toranc3]

Homework Statement

Two horses pull horizontally on ropes attached to a stump. The two forces F1= 1300 N and F2 that they apply to the stump are such that the net (resultant) force R has a magnitude equal to that of F1 and makes an angle of 90 with F1.

What is the magnitude of F2?

Homework Equations

The Attempt at a Solution

I got the answer correct but I was confused with the wording. F2 ended up being at some angle with respect to the x-axis and F1. I thought that this force was horizontal. Could somebody clarify this? Also could this be solved using the dot product?

θ=135
F2= 1838N

 

[Doc Al]

I got the answer correct but I was confused with the wording. F2 ended up being at some angle with respect to the x-axis and F1. I thought that this force was horizontal. Could somebody clarify this?

When they say that the horses pulled horizontally, they just mean that the ropes were parallel to the ground, not angling upward or downward.

If F1 is along the y-axis, then the resultant will be along the x-axis. You use that fact to solve for F2. (The x-y plane is the plane of the ground.)

How did you solve it?

 

[Toranc3]

When they say that the horses pulled horizontally, they just mean that the ropes were parallel to the ground, not angling upward or downward.

If F1 is along the y-axis, then the resultant will be along the x-axis. You use that fact to solve for F2. (The x-y plane is the plane of the ground.)

How did you solve it?

Fy:

F=ma

ma=R
F2sin(theta) =1300N


Fx:

F=ma
F1+F2cos(theta) =ma

ma=0

-F1/cos(θ) =F2

I substituted this into the Fy. I am not sure if this is the correct way to do it though.

 

[Doc Al]

Fy:

F=ma

ma=R
F2sin(theta) =1300N


Fx:

F=ma
F1+F2cos(theta) =ma

ma=0

-F1/cos(θ) =F2

I substituted this into the Fy. I am not sure if this is the correct way to do it though.

Please define your directions. Where is F1 pointing? What's θ?

Instead of F = ma, just use ƩF = whatever. There's no acceleration involved, just adding forces.

 

[Toranc3]

Please define your directions. Where is F1 pointing? What's θ?

Instead of F = ma, just use ƩF = whatever. There's no acceleration involved, just adding forces.

Yeah I did it over again with just forces. Thanks for your help.