Review 1. What units would you use to describe the speed of a
car? Would you use different units for the speeds of
runners in a neighborhood race? Explain.
2. In a skateboarding marathon, the winner covered 435 km
in 36.75 h. What was the winner's average speed?
3. Think Critically: Make a distance-time graph for a
2-hour car trip. The car covered 50 km in the first
30 minutes, stopped for 30 minutes, and covered 60 km
in the final 60 minutes. Note the three graph segments.
Which graph segment slopes the most? Which one does
not slope? What was the car's average speed?

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: