Aball with a mass of 160 g which contains 4.40×108 excess electrons is dropped into a vertical shaft with a height of 115 m . at the bottom of the shaft, the ball suddenly enters a uniform horizontal magnetic field that has a magnitude of 0.200 t and direction from east to west. if air resistance is negligibly small, find the magnitude of the force that this magnetic field exerts on the ball just as it enters the field. use 1.602×10−19 c for the magnitude of the charge on an electron.

Explanation:

To find the force we proceed by defining the variables we have,

The charge on one of the balls is defined under the equation,

Due to the height we need to calculate the potential energy at the height of 115m,

The kinetic energy would be given by

From the law of conservation we equate the two equations

In this way we now calculate the strength of the particle

a solenoid is created by wrapping a l = 90 m long wire around a hollow tube of diameter d = 4.5 cm.   the wire diameter is d = 0.9 mm.   the solenoid wire is then connected to a power supply so that a current of i = 9 a flows through the wire.

randomized variablesl = 90 m

d = 4.5 cm

d = 0.9 mm

i = 9 a                                          

write an expression for the number of turns, n, in the solenoid. you do not need to take into account the diameter of the wire in this calculation.

calculate the number of turns, n, in the solenoid.

write an expression for the length of the solenoid (l2) in terms of the diameter of the hollow tube d.

calculate the length of the solenoid (l2)   in meters.

calculate the magnitude of the magnetic field at the center of the solenoid in teslas.

explanation:

grav force prop 1/r squared 2r all squared is 4rsquared 1/4rsquared quartered