A simple pendulum with a period T = 2.50 s is attached to the ceiling of an elevator which is initially at rest.

a. Calculate the period of oscillations when the elevator begins to accelerate upwards with acceleration a = 1.50 m/s^2.
b. Calculate the period of oscillations when the elevator accelerates downwards with acceleration a = 2.50 m/s^2 .

Explanation:

For a simple harmonic motion, the period, T = 2π ∙ √( L / g )

When the elevator is at rest:

2.5 = 2π * √( L/9.81)

L = 1.5515 m.

B.

When the elevator is accelerating upwards at 1.5 m/s²

T = 2π ∙ √( 1.5515/(9.81 + 1.5))

= 2.33 s.

B.

When the elevator is accelerating downwards at 2.5 m/s²

T = 2π * √(1.5515/(9.81 - 2.5))

T = 2.89 s.

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:

does anyone know or what?