00:01
Hello student, to solve this question, let us write the formula for magnetic force fb, which is equal to qv vector cross b vector.
00:09
It can be also written as qvb when there is theta equals 90 degree.
00:15
Also, the centripetal force fc can be written as mv squared divided by r.
00:21
Now from here, firstly, let us calculate part a, which is that is radius of path of the electron.
00:28
So using the centripetal force, here, here, here which will be equal to the magnetic force.
00:33
So the relation will become mv squared divided by r equals qu vb.
00:40
So from here we can find the value of r which will be equal to mv divided by qb.
00:48
So putting the values given in the statement we get mass of an electron is 9 .1 into 10 to power minus 31.
00:56
Multiply by speed is given 2 into 10 to power 6.
01:00
Meter per second divided by charge on electron is 1 .6 into 10 to power minus 19 multiplied by magnetic field is given 2 into 10 to power minus 4 tesla.
01:13
So from here we can find the answer for radius which will be 5 .69 multiplied by 10 to power minus 2.
01:22
So the final answer for part a will be radius which is equal to 5 .69 multiplied by 10 to power minus 2 meters.
01:32
Now for part b we need to firstly calculate the magnetic force for part 1 which can be calculated using the same results so putting here fb equals q is given in that is 1 .6 into 10 as 10 minus 19 multiplied by v vector is given as 2 .5 multiply by 10 as to power 5 j then cross product with the b vector which is given as 0 .05i.
02:04
Now after solving this relation we get the magnetic force vector that is fb vector will be equal to minus 0 .2k unit vector newton.
02:18
So the final answer that is the magnitude of fb from here will be equal to fb is 0 .2 newton.
02:27
Now we need to calculate the acceleration for part 2, which will be given as acceleration a will be equal to force fb divided by mass m...