A braking car on dry pavement has a constant acceleration of -6.0 m/s Skid marks created are 33.3 m long. The driver claims that he was going 36 km/h.
Which of the following statements is true?

36 km / hr * (1000 m  / km)  / (3600 sec / hr)  =  10 m/s

2 a s = Vi^2        relation between initial velocity and acceleration

s = 10^2 / (2 * 6) = 8.3 m  

Should have been able to stop in 8.3 m at 36 km / hr not 33.3 m

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:

0.55x745.7j and a calculator