Calculating the Magnitude of the force

[kkingkong]

Homework Statement

Calculate the magnitude of the force on an electron moving at 4×10^6 m/s at an angle of 8 degrees to a magnetic field of 0.3 Tesla. Give your answer in Newtons.

Homework Equations

the equation that i used was f= qvBsin(8)

The Attempt at a Solution

f = 1.602 E-27(4E6)Sin 8
but i keep getting the wrong answer, what am i doing wrong ,. PLease help me. Thanks

 

[vela]

It looks like you didn't include B.

 

[kkingkong]

oh thank you after i include B i still get the wrong answer. i get 2.68E-22

 

[vela]

I just noticed you're not using the right value for q, and make sure your calculator is in degrees mode.

 

[HalfLostAndSearching]

Hi there,

First of all, it looks like you are on the right track using the equation f = qvBsinθ, where q is the charge of the electron, v is its velocity, B is the magnetic field, and θ is the angle between the direction of the electron's velocity and the direction of the magnetic field.

However, there are a few things to note in order to arrive at the correct answer. First, make sure that all of your units are consistent. The charge of an electron, q, is usually given in Coulombs (C), while the velocity, v, is given in meters per second (m/s). Therefore, you will need to convert the charge to Coulombs by multiplying by 1.602 x 10^-19 C/e, where e is the elementary charge. This will give you the correct units for the force, which is Newtons (N).

Next, double check the values you are plugging into the equation. The velocity given in the problem is 4 x 10^6 m/s, which is a very high speed for an electron. Make sure you are not accidentally using 4 x 10^6 m/s as the velocity of light (c) instead. Also, check to make sure that the angle is in degrees and not radians. If you are using a scientific calculator, you may need to convert the angle to radians by multiplying by π/180.

Finally, once you have double checked your values and units, plug them into the equation and solve for the force. The answer should be in the range of 10^-14 N, which is a very small force due to the small mass of an electron.

I hope this helps, and good luck with your calculations!