You want to heat 1 kg of water 10 degrees celsius and you have the following methods under consideration. The heat capacity of water is 4.184 J/K g.
(a) You can heat it with a mechanical eggbeater that is powered by a 1-kg mass on a rope over a pulley. How far does the mass have to descend in the earth's gravitational field to supply enough work?
(b) You can send 1 A through a 100 ohm resistor. How long will it take?
try to think about it you stupid cun
To calculate the amount of work required to heat the water, we can use the formula:
Work = Heat capacity * Mass * Temperature change
In this case, the heat capacity of water is given as 4.184 J/K g, the mass of water is 1 kg, and the temperature change is 10°C.
(a) Using a mechanical eggbeater:
To heat the water with a mechanical eggbeater, we need to calculate the work required. However, it is not clear how the eggbeater is linked to the mass on the rope and the pulley. Can you provide any additional information about the system?
(b) Sending 1 A through a 100 ohm resistor:
To calculate the time it takes to heat the water using an electric current passing through a resistor, we can use the formula:
Time = Heat energy / (Power = Current^2 * Resistance)
In this case, the heat energy required is given by Heat capacity * Mass * Temperature change, and the resistance is 100 ohms. The current passing through the resistor is given as 1 A.
So, to solve for time:
1. Calculate the heat energy required:
Heat energy = Heat capacity * Mass * Temperature change
2. Calculate the power:
Power = Current^2 * Resistance
3. Divide the heat energy by the power to get the time:
Time = Heat energy / Power
Substitute the given values and calculate the time required to heat the water using the electric current passing through the resistor.