What will be the final temperature of 120.0 g of 20.0°C water when 100.0 g of 50.00°C iron nails are submerged in it?
(The specific heat of iron is 0.460 J/(g·°C).)

The final temperature will be 22.52°C.

Explanation:

Let the final temperature be T°C.

Heat gained by water = 120 × 4.186 × (T - 20)

                                    = 502.32 (T-20)

Heat lost by iron nails = 100 × 0.460 × (50 -T)

                                    = 46 (50-T)

As we know,

                         Heat lost = Heat gained

                   or, 46 (50-T) = 502.32 (T-20)

                  or, 2300 - 46T = 502.32T - 10046.4

         or, (2300 + 10046.4) = (502.32 + 46) T

                                    or, T =  

                                    ∴ T = 22.52°C

Hence the final temperature of the system is 22.52°C.

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: