1500W thingy heats1.5kg water from 18C to 59C in 3.0minutes. How mcuh n-ergy was used by the thingy?
There are two ways to do this and they should agree, if all of the electrical power goes into heating the water. Let's see if they do.
Power consumed by the "thingy" is 1500 J/s * 3.0 min * 60 s/min = 270,000 J
Q = Change of water's internal energy
= m C *delta T
= 1500 g* (1.0 cal g/C)*41 C *4.18 J/cal= 257,070 J
The latter number is more reliable. The 1500 W rating of the heater may have not been quite been reached due to low voltage, or heat transferred to other regions
To calculate the energy used by the "thingy," you can use the formula:
Energy = Power × Time
Here, the power is given as 1500W (watts) and the time is given as 3.0 minutes.
Before we proceed with the calculation, we need to convert the time from minutes to seconds since power is given in watts, and time should be in seconds for consistent units. There are 60 seconds in a minute, so we have:
Time = 3.0 minutes × 60 seconds/minute = 180 seconds
Substituting the values into the formula, we have:
Energy = 1500W × 180s
Energy = 270,000 joules (J)
So, the "thingy" used 270,000 joules of energy to heat the water.