Problem:(adsbygoogle = window.adsbygoogle || []).push({});

A man mows his lawn and pushes the mower at a constant speed. The effective coefficient of kinetic friction between the mower and the lawn is 0.40. He pushes on the lawn mower handle at an angle of 45 degrees to the horizontal. (Assume the lawn surface is horizontal.) The mower has a mass of 25 kg. Solve for the normal force acting on the lawn mower, the effective kinetic friction acting on the lawn mower, and the magnitude of the force exerted by the man.

I keep getting stuck in my equations because I don't have enough information. The normal force I have calculated by multiplying the mass (m) by the acceleration due to gravity (professor told us to use 10 instead of 9.8 for simplicity), then subtracting that number from itself multiplied by the sine of 45 degrees. This gave me 426.78 N for the normal force.

I used this value, despite my doubts at its accuracy, to find the kinetic friction. I multiplied the friction coefficient (0.40) by the normal force (426.78 N hopefully) and got the value 170.71 N.

Finally I tried solving for the force exerted by the man and completely confused myself. Physics is an enigma to me. Help would be tremendously appreciated.

**Physics Forums | Science Articles, Homework Help, Discussion**

Dismiss Notice

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Homework Help: Midterm Today- Help calculating friction and forces PLEASE!

**Physics Forums | Science Articles, Homework Help, Discussion**