Download Name Date_____________________ Per. ______ HW Physics

Name _______________________________________ Date_____________________ Per. _________
HW Physics Magnetic force and Particle Motion
1. A positive charge of 0.25C moves horizontally to the right at a speed of 2.0x102 m/s and enters a
magnetic field directed vertically downward. If it experiences a force of 20N, what is the
magnetic field strength?
2. An electron (1.6 × 10-19 C) moves south at a velocity of 1.2 x 105 m/s and has a magnetic force of
2.2 x 10-10 N exerted on it. If the magnetic field points downward, what is the magnitude of the
magnetic field?
3. A charge of 0.050C moves vertically in a field of 0.080T that is oriented horizontally. What
speed must the charge have to experience a force of 10N?
4. A singly charged positive ion (3.2 × 10-19 C) has a mass of 6.68 × 10–27 kg. After being
accelerated through a potential difference, it has a velocity of 5.66 × 104 m/s. The ion then enters
a magnetic field of 0.500 T, in a direction perpendicular to the field. Calculate the magnitude of
the magnetic force on the ion.
5. A beam of protons (mp = 1.672 × 10-27 kg) is accelerated to a speed of 5.0x106 m/s in a particle
accelerator and emerges horizontally from the accelerator into a uniform magnetic field. What B
field would cancel out the force of gravity and keep the beam of protons moving in a straight
line? (Hint: Gravitational force must equal Magnetic force)
6. A proton (1.60 × 10-19 C), with a mass of 1.672 × 10-27 kg, travels with a speed of 3.0 × 106 m/s
perpendicular with the direction of a magnetic field of 0.30 T. What are:
(a) the magnitude of the magnetic force on the proton
(b) the proton’s acceleration?
7. A proton (1.60 × 10-19 C), with a mass of 1.672 × 10-27 kg, travels with a speed of 1.90 × 104 m/s
at an angle of 37° with the direction of a magnetic field of 0.85 T. What are:
(a) the magnitude of the magnetic force on the proton
(b) the proton’s acceleration?