A 5.18x10^4 kg railroad car moves on a frictionless horizontal rails until it hits a horizontal spring stopper with a force constant of 4.21x10^5 N/m. When the railroad car comes to a complete stop, the compression of the spring stopper is 32 cm. How fast was the railroad car initially?

The initial velocity of the cart was 0.91m/s.

Explanation:

When the car comes to a stop it has delivered all of its kinetic energy to the spring; therefore,

solving for we get:

we put in , , and to get:

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:

answer: (431,2)

step-by-step explanation: