Activity 2. Magnetic force on a moving charge 1. A particle with the same charge as an electron experiences a force of 5.2 x 10-12N and traveling at a speed of 4.21 x 107m/s at right angles to a magnetic field. a. How strong is the magnetic field? b. What does its acceleration if its mass is 1.88 x 10-28 kg? 2. A force of 5.78 x 10-16N acts on an unknown particle moving at an angle of 90° through a magnetic field. If the velocity of the particle is 5.65 x 104 m/s and 3.20 x 10-2 T, how many elementary charges does it carry?

An alpha particle ( Helium nucleus) having a mass of 4 protons is shot into a magnetic field of 0.2 T at right angles to the field and moves in a circle of radius 20 cm. Find a) the momentum of the alpha particle b) its velocity c) kinetic energy.

*42. A bar magnet is divided into two pieces. Which of the following statements is true about the force between the broken pieces if they face each other with a small separation? Group of answer choices There is an electric attractive force between the broken pieces. There is an electric repulsive force between the broken pieces. There is a magnetic attractive force between the broken pieces. There is a magnetic repulsive force between the broken pieces.

2. A proton with energy of 5.7 MeV enter the magnetic field B = 0.75 T perpendicularly to magnetic field lines (0 = 90°) a) What is the speed of the proton? (leV = 1.6x10-19 D (K = ½ mv²) b) What is the force on the proton? c) What is the radius of its rotations?