You wish to boil 1.9 kg of water, which has a specific heat capacity of 4186 j/kg-k. the water is initially at room temperature (293 k). water boils at 373 k.
1) how much energy must be added to the water by heating it in order for it to start boiling?

6.36 105 J

Explanation:

In calorimetry all the energy given to a system is converted to heat and the equation for heat is

     Q = m   ΔT

The temperature can be in degrees Celsius or Kelvin since the interval between them is the same, substitute and calculate

Q = 1.9 4186 (373-293)  

Q = 6.36 105 J  

This heat equals the energy supplied

the minimum amperage that the current in this wire would have to have so that its weight is completely supported by the magnetic force due to earth's field, assuming that no other forces except gravity act on it

i already answered it by 34/s