# Proton in magnetic and electric field

• syhpui2
In summary, a proton moving in the +x direction with speed v is in a uniform magnetic field, B, and a uniform electric field, E. The question asks for the required orientation of the electric field for the proton to move un-deflected. The answer is that the electric field should be in the -y direction. The solution was found using RHR and considering the direction of the B field pushing on the proton.

## Homework Statement

As shown in the figure below, a proton moves in the +x direction with speed v and is immersed in both, a uniform magnetic field, B, oriented in the -z direction, and a uniform electric field, E (not shown in the diagram). What electric field orientation is required in order for the proton to move un-deflected through the combined magnetic and electric field region?
(a) +y direction
(b) -y direction
(c) +z direction

http://i.imgur.com/1G80T.png

qE=qVB

## The Attempt at a Solution

I used RHR, I get answer A...

Which way does the B field push on the proton?
Which way should the E field push on it?

Delphi51 said:
Which way does the B field push on the proton?
Which way should the E field push on it?

Which way does the B field push on the proton? Along x-axis
Which way should the E field push on it? Opposite direction of qvb?

## 1. What is a proton?

A proton is a subatomic particle that has a positive electrical charge and is found in the nucleus of an atom. It is one of the building blocks of all matter in the universe.

## 2. What is a magnetic field?

A magnetic field is an area in space where a magnetic force can be observed. It is created by moving electric charges, such as those found in magnets or electric currents.

## 3. What is an electric field?

An electric field is an area in space where an electric force can be observed. It is created by stationary or moving electric charges and can be manipulated by electrically charged objects.

## 4. How does a proton interact with a magnetic field?

A proton has a magnetic moment, which means it behaves like a tiny magnet. When placed in a magnetic field, it will either align with the field or rotate around it, depending on the strength and direction of the field.

## 5. How does a proton interact with an electric field?

A proton has an electric charge, so it will experience a force when placed in an electric field. The direction and strength of the force depend on the strength and direction of the electric field, as well as the charge and velocity of the proton.