Force in a magnetic field. Need help using the equation

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SUMMARY

The discussion focuses on calculating the force per meter on a straight wire carrying a 6.70-A current in a 0.89-T magnetic field using the equation F = IlBsinθ. For a 90-degree angle, the correct force is 5.9 N/m. The user struggles with calculating the force at a 45-degree angle, initially obtaining 5.07 N/m, which is incorrect due to improper use of the sine function. The correct approach involves converting degrees to radians for accurate sine calculations.

PREREQUISITES
  • Understanding of the equation F = IlBsinθ
  • Basic knowledge of trigonometric functions, specifically sine
  • Familiarity with units of current (Amperes) and magnetic field strength (Tesla)
  • Ability to convert degrees to radians
NEXT STEPS
  • Review trigonometric functions and their applications in physics
  • Practice converting angles from degrees to radians
  • Explore the implications of magnetic fields on current-carrying conductors
  • Learn about the right-hand rule for determining force direction in magnetic fields
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Students studying physics, particularly those focusing on electromagnetism, as well as educators seeking to clarify concepts related to forces in magnetic fields.

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Homework Statement



What is the magnitude of the force per meter of length on a straight wire carrying a 6.70-A current when perpendicular to a 0.89-T uniform magnetic field?

What if the angle between the wire and field is 45.0°?

I know how to do the whole thing, I just can't get my answer right. I don't know if I am working the equation out right.

Homework Equations



F=IlBsin[tex]\theta[/tex]

The Attempt at a Solution



Using the above equation. For part A I know that I use it for 90 degrees at 1m

F=(6.70A)(0.89T)sin90=5.9N/m

Part B is the one I can't get the answer to.

F=(6.07A)(0.89T)sin45

**I haven't had a trig class or a physics class for about 7 years so I don't remember how to exactly use sin. For Part A I got the correct answer because I just didn't use the sin. I just took the (6.70A*0.89T). Can someone explain how to use sin or how to get the right answer. I got 5.07 N/m but that is not correct.

Thanks in advance to everyone that helps.
 
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It sounds like you had your calculator set to radians instead of degrees.

1 degree = pi/180 radians so 45 degrees= 45pi/180 =pi/4 radians

Try using that as your argument for sin.
 

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