Which object moves in simple harmonic motion? \

a stretched rubber band with an mass
b rolling ball going down a hill
c moving car
d orbiting satellite

Explanation:

Simple harmonic motion requires a restoring force.

Simple harmonic motion should be periodic.

Option A:

When a rubber band is stretched,the internal forces of the rubber band pulls the band inside.So,internal forces are the restoring forces in a rubber band.

The motion is periodic as well since the the rubber band makes to an fro motion expanding ans contracting.

So,this performs SHM.

Option B:

There is no restoring force and no periodicity.

So,this is not SHM.

Option C:

There is no restoring force and no periodicity.

So,this is not SHM.

Option D:

There is periodicity but no restoring force.

So,this is not SHM.

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: