At a Particular Instant,a Proton Moves Toward the East in a Uniform

question 136

Multiple Choice

At a particular instant,a proton moves toward the east in a uniform $\vec { B }$ field that is directed straight downward.The magnetic force exerted on it is

• A)zero.
• B)upward.
• C)toward the north.
• D)toward the south.
• E)downward.