# Homework Help: Mechanical Advantage Help

1. Sep 16, 2016

### Armando Valle

What is the mechanical advantage of a nail puller where you exert a force 45 cm from the pivot and the nail is 1.8 cm on the other side? What minimum force must you exert to apply a force of 1250 N to the nail?

2. Relevant equations
2. Relevant equations
MA= FO/FI * LI/LO

3. The attempt at a solution
Ive tried to make the problem but i dont understand it, can someone help me? thanks!

2. Sep 16, 2016

### Staff: Mentor

What have you tried? What's the geometry of a nail puller? Have you drawn a diagram and labelled the forces? A "pivot" implies that torques may be involved. What have you done to investigate this?

3. Sep 16, 2016

### Armando Valle

Ive tried to use the MA equation but i don´t find a relationship with the forces included on the problem. this are the images of the problems, thanks!

#### Attached Files:

• ###### Screen Shot 2016-09-16 at 6.36.46 PM.png
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4. Sep 16, 2016

### Staff: Mentor

I don't understand your relevant equation ("MA equation") as presented. Can you define the variables?

5. Sep 16, 2016

### Armando Valle

this are the equations

#### Attached Files:

• ###### Screen Shot 2016-09-16 at 6.57.44 PM.png
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52.1 KB
Views:
441
6. Sep 16, 2016

### Staff: Mentor

does not reflect what is in your latest image. It should be:

MA= FO/FI = LI/LO

Note the "=" between the terms. So you're dealing with ratios.

Can you pair up the given values in your problem with the variables in your equation?

7. Sep 16, 2016

### SammyS

Staff Emeritus
The figure for OP's problem together with said equations.