# Calculations involving DC Electric Motors, Magnietism and magnetic field strength

gaimesh

## Homework Statement

An electric motor has a square coil with 20 turns and an area of 150cm^2. the coil is free to rorate in uniform magnetic field of 300mT. If there is a DC current of 5.00A, passing through the coil: what is the maximum force on one side of the coil? and what is the maximum torque on the coil?

## The Attempt at a Solution

well i realized that there are 5 loops of this coil, i also figured that each turn is 7.5cm long. (150/4) = 37.5 (37.5/5) = 7.5cm, and I am not sure where to go from here.

## Answers and Replies

Science Advisor
Homework Helper
welcome to pf!

hi gaimesh! welcome to pf!
An electric motor has a square coil with 20 turns and an area of 150cm^2. the coil is free to rorate in uniform magnetic field of 300mT. If there is a DC current of 5.00A, passing through the coil: what is the maximum force on one side of the coil? and what is the maximum torque on the coil?

well i realized that there are 5 loops of this coil, i also figured that each turn is 7.5cm long. (150/4) = 37.5 (37.5/5) = 7.5cm, and I am not sure where to go from here.

uhh? there are 20 loops … and you can't divide an area by 4 to get a length!

try again, and start by writing out the formula you wish to use