Suppose a person whose mass is m is being held up against the wall with a constant tangential velocity v greater than the minimum necessary. find the magnitude of the frictional force between the person and the wall.

friction force must be equal to the magnitude of weight of the object

Explanation:

When the object is stuck against the wall

then we will have

also we know that

so if the block is at rest and not sliding then in vertical direction the force must be balanced

so here we can say

so friction force must be equal to the magnitude of weight of the object

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: