Static and Kinectic Problem Help

[globalcrook]

Homework Problem

A Worker is pulling a box and applies a force at an angle of 45 degress to the horizontal, how large must the force be to move the box

FBD:

n
| /
| / <----Angle in between is 45 degrees
O ------F cos 45
|
|
mg

Please help, confused about how to solve this problem
Thanx in advance

 

[Locrian]

Well since they didn't give you any values (I assume), you are going to leave everything as variables. Break the force down into components first, find the component in the x-direction necessary to be greater than the force of static friction, then rebuild your original force knowing that value.

Try it and post when you get stuck.