If an automobile engine delivers a power of 50.0 hp, how much time will it take for the engine to do 6.40 x 10^4 j of work? (1 hp= 746 w)

Given data

Power (P) = 50 hp,

                = 50 × 746,  we know that 1 hp = 746 W.

                = 37300 Watts      (Watt = J/s)  

Work  = 6.40 ×10⁴ J

Power is defined as rate of doing work and the unit of power is Watt.

Mathematically,

         Power = (Work / time)   Watts

                     = 6.40 ×10⁴ / time

          37300 W = 6.40 ×10⁴ J /time      (Where time in seconds)

         => time = Work/Power

                      = 6.40 ×10⁴/37300

                      = 1.74 seconds  

 Therefore , the engine need 1.74 seconds to do 6.40 6.40 ×10⁴ J of work

the one with the highest 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: