top of page
Writer's picturekeshprad

Barron's 2nd Edition PT1 Q52


52) This question asks us to find the direction of the magnetic force acting on the object just as it enters the magnetic field. In order to find this, we can use the right-hand rule for moving charges. There are many forms of the right-hand rule. If you are unsure about what the right-hand rule is, you can click here to read about it from Khan Academy.


Your middle finger(for magnetic field) would point in the -z-direction, and your pointer finger(for velocity) would point in the +x-direction. Then you would find that your thumb(for force) points in the +y-direction.

Where F is magnetic force, B is magnetic field, and v is velocity

However, we are not done yet. The right-hand rule would give us the magnetic force on a positive charge, but question 52 asks the direction of the force on a negative charge. All we need to do is flip the direction of the force, so instead of pointing in the +y-direction, it will point in the -y-direction.

Where F is magnetic force, B is magnetic field, and v is velocity

Answer: C

コメント


bottom of page