When you apply 1000 joules of energy to 50 grams of water its temperature changes to 30 degrees . What was the initial temperature in celsius?

25.2°C

Explanation:

Given parameters:

Energy applied to the water  = 1000J

Mass of water  = 50g

Final temperature  = 30°C

Unknown:

Initial temperature  = ?

Solution:

To solve this problem, we use the expression below:

            H  = m c Ф

H is the energy absorbed

m is the mass

c is the specific heat capacity

Ф is the change in temperature

     1000  = 50 x 4.184 x (30  -  initial temperature )

     1000  = 209.2(30 - initial temperature)

      4.78  = 30 - initial temperature

      4.78  - 30  = - initial temperature

         Initial temperature  = 25.2°C

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hope this : -)

tony (lordcaos066)