When opening a hinged door, the handle is usually on the side of the door farthest from the hinges. rank the difficulty of opening the door if you were to push or pull on the following locations on the door:

hardest to open

easiest open

1. as close to the hinges as possible

2. the center of the door

3. the edge farthest from the hinges

The order of difficulty from the hardest to the easiest would be subject to the concept we have of Torque.

The Torque principle defines us that

Where,

F = Force

d = Distance

As the distance increases, the force applied must be less to make the movement of the object so we have to

Hence we have to be the distance inversely proportional to the force to turn the door the order would be:

As close to the hinges as possible (Hardest)> The center of the door> the edge farthest from the hinges (Easies)

1>2>3

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: