How to calculate the power in watts

Do you have a device and want to calculate the amount of energy it will consume ? The level of mathematics needed to calculate the power and express it in watts is relatively high, so it is advisable to make these calculations with the calculator. This tutorial is important for anyone who wants to know the equations to calculate the power or learn how to calculate the vapor pressure.

You will need to:
  • Calculator
  • Number of seconds
  • Amount of Energy
  • Amount of current
  • Number of volts
  • Amount of Resistance
Steps to follow:

one

Using a calculator, determine the amount of energy (Joules) and the time (seconds) for which you want to calculate the power (watts) . Divide the energy by time and you will get the feed rate (watts) that is used. Example: 0.05 (J) / 20 (S) = 0.0025 (mW). It uses milliwatts because the amount of energy used mostly in electronics is relatively low.

two

Determine the amount of current (amps) and voltage (volts) for which you want to calculate the power. Multiplies the number of amps and volts together. The product will give you the amount of energy. For example: 0.001 (mA) x 5 (V) = 0.005 (mW)

3

Look at Ohm's law: V = I x R or voltage is equal to intensity per resistance. Using the formula above, the energy is equal to amps per voltage (p = I x V), converts the formula to energy equal to current intensity squared by resistance P = I x I x R. This will give you the calculation of the energy through resistance.

4

Finding the square of the voltage and dividing it by the resistance will also give you the amount of energy. For example: P = I x I x R = 0.005 (mA) x 0.005 (mA) x 50 (ohms) = 0.000025 (mA) x 50 (ohms) = 0.00125 (mW)

Tips
  • Do not use a calculator if you want to improve your mathematical calculations mentally. practice these equations by connecting power and calculate time, energy, volts, amps and resistance