Physics 1308 Quiz 4
Physics 1308 Quiz 4 Solution An electron experiences the greatest force as it travels 1.8× 106 m / s in a magnetic field when it is moving southward. The force is upward and the magnitude is 2.2×10−12 N . What is the magnitude and direction of the magnetic field? Up
F
E
B S
v
Using the right hand rule we can naively conclude that the direction of the magnetic field is east, but since the charge is negative (an electron) we choose the opposite direction: west. You can see also see this using the vectors depicted in the graph: v i × B =− F k . Again the opposite direction is taken since we have an electron. The magnitude of the magnetic field is : B=
F qv
=
2.2 ×10 −12 N 1.6× 10−19 C⋅1.8×10 6 m / s
Useful Equations: F B =q v × B , e− =−1.60×10−19 C
1/1
= 7.6T
F
E
B S
v
Using the right hand rule we can naively conclude that the direction of the magnetic field is east, but since the charge is negative (an electron) we choose the opposite direction: west. You can see also see this using the vectors depicted in the graph: v i × B =− F k . Again the opposite direction is taken since we have an electron. The magnitude of the magnetic field is : B=
F qv
=
2.2 ×10 −12 N 1.6× 10−19 C⋅1.8×10 6 m / s
Useful Equations: F B =q v × B , e− =−1.60×10−19 C
1/1
= 7.6T
