When 90 kJ is removed from a 2-kg copper bar its temperature drops from 200 degrees celcius to 85 degrees celcius what is the specific heat of the iron?

Q = M*C*(delta T)

Solve for C, with

deltaT = -115 C
Q = -90 kJ
M = 2.0 kg

0.391

0.39 kJ/kg degree C

To find the specific heat of the copper bar, we can use the equation:

Q = mcΔT

Where:
Q is the amount of heat transferred,
m is the mass of the copper bar,
c is the specific heat of copper, and
ΔT is the change in temperature.

In this case, we know that 90 kJ of heat is removed from a 2-kg copper bar, causing the temperature to drop from 200 degrees Celsius to 85 degrees Celsius.

First, we need to convert the given units to SI units.

90 kJ = 90,000 J

ΔT = (final temperature - initial temperature)

ΔT = (85°C - 200°C) = -115°C

Now, rearrange the equation to solve for c:

c = Q / (m * ΔT)

Substituting the given values:

m = 2 kg
Q = 90,000 J
ΔT = -115°C

c = 90,000 J / (2 kg * (-115°C))

c ≈ -783.3 J / (kg * °C)

Therefore, the specific heat of the copper bar is approximately -783.3 J / (kg * °C).