Torque on a coil question (1 Viewer)

[Roy216]

I have this question which i seem to keep getting the wrong answer even though i feel like I'm doing everything right...

I'm not sure whether I'm right or the answers have a typo (which isn't a surprise), can someone do it?

A 5cm square vertical loop with 50 turns of wire is in a magnetic field of intensity 0.2T such that the plane of the coil is at right angles to the field. The loop carries a current of 4.0 A.
(a) Calculate the magnitude of the force acting on each side of the coil.
(b) Calculate the maximum torque on the coil

 

[Parvee]

What are the answers from the book?

 

[Roy216]

(a) 4 x 10^-3 N
(b) 0.01 Nm

 

[Parvee]

I end up getting 2N for a) :/
and for b) you use torque=nBIAcostheta which gives 50x0.2x4x0.05^2x1= 0.1Nm

 

[Roy216]

yeah thats what i got aswell, im guessing the answers are wrong...

 

[SpiralFlex]

First question is just worded incorrectly, it's asking for the force acting on one loop of the coil.







Question 2 is the one that is stuffed up...

 

[Roy216]

but u still got (a) wrong its 0.004, well i managed the get all other 7 questions right, i think 1 has a typo im not sure

 

[Roy216]

and i forgot to add a similar question asked the same thing, i used the method for question 1 and i got it right

 

[kingkong123]

but u still got (a) wrong its 0.004, well i managed the get all other 7 questions right, i think 1 has a typo im not sure

no mate, for one coil its 0.04, not 0.004. which book is this from? surfing? cause i know that m&g surfing has a lot of wrong answers

 

[Roy216]

its no book, its a one notes file our teacher supplies, im not saying his wrong according to the actual answer, im saying his wrong according the answers provided