Author Question: A proton moving at a speed of 3.8 106 m/s cuts across the lines of a magnetic field at an angle of ... (Read 79 times)

HCHenry · **on:** Jul 28, 2018

A proton moving at a speed of 3.8 106 m/s cuts across the lines of a magnetic field at an angle of 40. The strength of the field is 0.25 10-4 T. What is the magnitude of the force acting on the proton? (qp = 1.6 10-19 C)
a. 1.4 10-17 N
c. 9.8 10-18 N
b. 2.3 10-17 N
d. 5.1 10-18 N

Question 2

A balloon of negligible mass is filled with 300 m3 of helium. How big a payload can the balloon lift? (The density of air is 1.29 kg/m3; the density of helium is 0.18 kg/m3.)
a. 150 kg
c. 333 kg
b. 300 kg
d. 444 kg