# Calculating the Magnitude of the force

• kkingkong
In summary, the task is to calculate the magnitude of 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. The equation used is f = qvBsin(8), with q being 1.602 E-27. The answer obtained is 2.68E-22, but make sure to include B and use the correct value for q, and check that the calculator is in degrees mode.
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

Last edited:
It looks like you didn't include B.

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

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

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!

## 1. What is the equation for calculating the magnitude of the force?

The equation for calculating the magnitude of the force is F = m x a, where F is force, m is mass, and a is acceleration.

## 2. How do you determine the direction of the force when calculating magnitude?

The direction of the force can be determined by using vector notation, where the force is represented by an arrow pointing in the direction of its action.

## 3. What units are used to measure force?

The SI unit for force is Newtons (N), but other commonly used units include pounds (lbs) and dyne (dyn).

## 4. Can the magnitude of the force be negative?

Yes, the magnitude of the force can be negative if the direction of the force is opposite to the direction of motion.

## 5. How can I calculate the magnitude of the force if I only have the mass and velocity?

You can use the formula F = m x v^2 to calculate the magnitude of the force when given mass (m) and velocity (v).

• Introductory Physics Homework Help
Replies
4
Views
335
• Introductory Physics Homework Help
Replies
4
Views
889
• Introductory Physics Homework Help
Replies
3
Views
785
• Introductory Physics Homework Help
Replies
3
Views
322
• Introductory Physics Homework Help
Replies
5
Views
1K
• Introductory Physics Homework Help
Replies
7
Views
331
• Introductory Physics Homework Help
Replies
10
Views
1K
• Introductory Physics Homework Help
Replies
17
Views
908
• Introductory Physics Homework Help
Replies
6
Views
2K
• Introductory Physics Homework Help
Replies
4
Views
661