A system has 600 j of heat and does 300 j of work. What is the change in internal energy?

The final energy is 1,700 J

Explanation: According to first law of thermodynamics:

=Final energy-initial energy=Change in internal energy

q = heat absorbed or released

w = work done by or on the system

w = work done by the system=  {Work done by the system is negative as the final volume is greater than initial volume}

q = +500J   {Heat absorbed by the system is positive}

w = work done by the system = -300J

Explanation:

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:

see earlier answer