Julie walked to her friend's house to spend the afternoon. she walked at 4
mph. when she went home, she ran at 6 mph so she wouldn't be late. what is
true about her average speed and average velocity?

Julies average speed was 5 mph and her average velocity was 0 mph.

Explanation:

The average speed is (4 mph + 6mph) / 2.

It represents Julie's speed of walking in average. If Julie had gone and returned at a speed of 5 mph she would have used the same total travel time.

The average velocity represents the difference between the initial and final position divided by the travel time. As the initial and final positions are the same, the average velocity is zero.

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:

compass can be used day and night, cloudy or sunny