A charge of -7.2 µC is traveling at a speed of 7.8 106 m/s in a region of space where there is a magnetic fie

A charge of -7.2 µC is traveling at a speed of 7.8 E6 m/s in a region of space where there is a magnetic field. The angle between the velocity of the charge and the field is 54°. A force of magnitude 4.1 E-3 N acts on the charge. What is the magnitude of the magnetic field?

The force experience by charge (q) in magne field (B) is

F = q V cross B (vector form)
F = q v B sin (theta)
its direction is given by right hand rule
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N cross M = vector product = |N| |M| sin (Theta) r-hat(1 vector)
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|F| = 7.2*10^-6* 7.8*10^6 |B| sin (54°)
4.1*10^-3 = 45.433 |B|

|B| = 4.1*10^-3 / 45.433
|B| = 9.024 * 10^-5 Tesla
magnitude of mag field