- #1

stackptr

- 10

- 3

## Homework Statement

What minimum time is required to move a weight of mass 50 kg over a distance of 10 meters along a horizontal floor if the rope used to pull it breaks when the tension exceeds 20kgf, while a force of 10kgf is sufficient to start the weight moving or move it uniformly, overcoming the force of friction?

## Homework Equations

$$v = \frac{x}{t} = at = \frac{\Sigma F}{m}t$$

Where ##v## is the velocity of the object, ##x## is the horizontal distance covered, ##t## is the time in motion (what we are trying to solve for), ##a## is acceleration of the object and ##\Sigma F## is the net force on the object.

## The Attempt at a Solution

[/B]

I rearranged the equation for ##t##, giving me

$$t = \sqrt{\frac{mx}{\Sigma F}}$$

However, I am having trouble figuring out the net force. I know the tension is acting to the right with a force of 10kgf, and I know ##f_s\leq10 kgf##. What would the kinetic friction be though? Using this, I can do ##T-f_k## to find the net force on the object.