Question

a.     A proton (q=+5x10^-19C) is injected from right to left into a field B of 0.5 T directed toward the upper side of a sheet of paper. If the velocity of the proton is of 4x10⁶m/s, find the magnitude and direction of the magnetic force over the proton.

b.      A wire 50 cm long conducts a current of 1A forming an angle of 35° to the north of a magnetic field directed toward east. Find the magnitude of the magnetic field so that a force of 17N can be exerted over the wire. Find the direction of the force.

Answer 1

$F= Force\\q= charge\\v= velocity \\B=magnetic\>field\\\theta \> =$

angle between the particle and the magnetic field

Then:

$F=qvBsin\theta$

$F= 5×10^{-19}×4×10^6×0.5 sin90$

$F=1×10^{-12}\>N$

Part 2

$F=\Iota lBsin\theta$

Where

$F= Force\\\Iota=current\\L=$length of conductor

$B$ =manetic field

$B=\frac{17}{1×0.5×sin35}$

=$59.28 T$

Force will be directed upward.