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The self-inductance of a solenoid is given by:

where

is the vacuum permeability
N is the number of turns
A is the cross-sectional area of the solenoid
l is the length of the solenoid
For the solenoid in our problem, N=3000, l=70.0 cm=0.70 m and the self-inductance is L=25.0 mH=0.025 H, therefore the cross-sectional area is

And since the area is related to the radius by

The radius of the solenoid is
Frequency is 1/period. f=1/0.5 = 2Hz
True, the manipulated variable is plotted on the horizontal axis
Answer:
6.67km/hr²
Explanation:
Given parameters:
Velocity = 40km/h
Time = 6h
Unknown:
Acceleration = ?
Solution:
Acceleration is the rate of change of velocity with time.
Acceleration =
v is the final velocity
u is the initial velocity
t is the time
Acceleration =
= 6.67km/hr²