Calculating Thermal Energy Supplied by Heater in 30.0s - Kilo-joules

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Ohm's Law to calculate the power usage (voltage times current) and noted that energy = power times time. In summary, the heater with a resistance of 15.0 W and operating on 120.0 V supplies a thermal energy of 450 J or 0.45 kJ in 30.0 seconds. This was calculated using Ohm's Law and the formula for energy transfer.
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A heater has a resistance of 15.0 W. It operates on 120.0 V. What thermal energy is supplied by the heater in 30.0 seconds? Answer must be in Kilo-joules.


Well o_o ..it would be nice if you could try to help me with this question. Since I recently moved from Germany to the U.S. with my parents.. and we weren't at this point in my old school.
 
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Do you mean 15 Ohms resistance?

Use Ohm's Law to calculate the power usage (voltage times current) and note that energy = power times time.
 
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questionmaster said:
A heater has a resistance of 15.0 W. It operates on 120.0 V. What thermal energy is supplied by the heater in 30.0 seconds? Answer must be in Kilo-joules.

Voltage (volts) = Current (amps) x Resistance (ohms)
Power (watts) = Voltage (volts) x Current (amps)

Therefore:
Resistance (ohms) = Power (watts)

Energy Transfer (J) = Power (W) x Time (s) => E = 15 x 30
=> Answer should be 450 J or 0.45 kJ.

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What is thermal energy?

Thermal energy is the energy that an object or substance possesses due to its temperature. It is a form of kinetic energy that results from the movement of particles within a material.

What is a heater?

A heater is a device that uses electrical or fuel energy to generate heat. It is commonly used to raise the temperature of a room or to heat water or other substances.

What is the unit of measurement for thermal energy?

The unit of measurement for thermal energy is the joule (J). However, in larger contexts, the kilo-joule (kJ) is often used. 1 kJ is equal to 1000 J.

How do you calculate thermal energy?

Thermal energy can be calculated by multiplying the mass of a substance by its specific heat capacity and the change in temperature. The formula is Q = m x c x ΔT, where Q is the thermal energy, m is the mass, c is the specific heat capacity, and ΔT is the change in temperature.

How do you calculate thermal energy supplied by a heater in 30.0 seconds?

To calculate the thermal energy supplied by a heater in 30.0 seconds, you would first need to know the power of the heater in watts (W). Then, you can use the formula Q = P x t, where Q is the thermal energy, P is the power, and t is the time in seconds. Make sure to convert the power to joules per second (J/s) before plugging it into the formula.

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