Magnitude and direction of the resultant force

AI Thread Summary
The discussion focuses on calculating the resultant force and velocity from given forces and motion scenarios. For the forces exerted on a box, the resultant force was determined to be 142.6 N at an angle of 165.2 degrees using vector components. In the boat scenario, the resultant velocity was calculated as 8.5 m/s at 289.3 degrees, with momentum found to be 1623 kgm/s. It was noted that the direction of momentum should align with the velocity direction. The participant indicated a commitment to engaging in physics discussions on the forum.
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1. Three ropes are tied to a box and three boys exert the following forces:
F1=220 N @ 90 degrees
F2=185 N @ 165 degrees
F3=235 N @280 degrees

Determine the magnitude and direction of the resultant force.


For my solution I made a Vector Componant table, found the total force on the x and y axis. Transferred that to a diagram and found the resultant force to be 142.6 N in a direction of 165.2 degrees.

2. You head across the Battle River in your boat with a velocity of 8.0 m/s, south. The river is flowing at 2.8 m/s, east.

a) Determine the magnitude and the direction of the resultant velcity vector.
b)Assume that you and you boat have a total mass of 192 kg. Calculate the direction of the momentum of you and your boat as you cross the river.


This question seemed to be really simple. I got the resultant velocity to be 8.5 m/s in a direction of 289.3 degrees. For the next part I found the momentum to be 1623 kgm/s, and wouldn't the direction be the same as the velocity?
 
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Yeah, I didn't check it but it looks as though everything is correct. For the boat you should include the direction (i.e. 19.3 degrees east of south or whatever the angle was relative to).
 
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Alright Thanks, and a little heads up for everyone here. I'll be one these forums alot, because I'm taking Physics by correspondance.
 
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