The specific heat of water is 4.18 J/(g·°C). How much energy is necessary to raise 15 g of water by 20 °C? (Use the equation Q = mcpΔT )

1254 J

Explanation:

Applying,

Q = mcpΔT Equation 1

Where Q = heat, m = mass of water, cp = specific heat capacity of water, ΔT = Change in temperature.

From the question,

Given: m = 15 g, cp = 4.18 J/(g.°C), ΔT = 20°C

Substitute these values into equation 1

Q = 15×4.18×20

Q = 1254 J

Hence the amount of energy required is 1254 J

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