A furnace supplies 28kW of thermal power at 300C to an engine and exhausts waste energy at 20C. At the very best, how much work could we expect to get out of the system per second

The amount of work we could expect to get out of the system per second = 28,000J/s

Explanation:

Given the power supplied to the system as  28kW;

Energy = power / time

At very best, the amount of work we could expect to get out of the system per second = 28,000 W / 1 second =  28,000J/s

Therefore, for a a furnace which supplies 28kW of thermal power at 300C to an engine and exhausts waste energy at 20C.

At the very best, the amount of work we could expect to get out of the system per second = 28,000J/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:

e/c, where e is its total energy