A car is moving at 20 m/s. The driver steps on the gas pedal and accelerates the car for 4 seconds at an acceleration of 4 m/s2. How fast is the car moving after it accelerates?

The final velocity of the car is 36 m/s.

Explanation:

Given;

initial velocity of the car, u = 20 m/s

time of the car acceleration, t = 4 s

acceleration of the car, a = 4 m/s²

the final velocity of the car is calculated as;

v = u + at

where;

v is the final velocity of the car

v = 20 + (4 x 4)

v = 36 m/s

Therefore, the final velocity of the car is 36 m/s.

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: