Table of Contents

- 1 What equation could you use to calculate energy use by an appliance if you knew the voltage current and time during which the current flows?
- 2 How do you calculate watts from volts and amps?
- 3 How do you find current in a circuit?
- 4 How do you calculate amps in a circuit?
- 5 How do you calculate the power in an electric circuit?
- 6 How do you check the wattage of a 110V appliance?

## What equation could you use to calculate energy use by an appliance if you knew the voltage current and time during which the current flows?

The power of an electric device, such as a hair dryer, can be calculated if you know the voltage of the circuit and how much current the device receives. The following equation is used: Power (watts) = Current (amps) × Voltage (volts)

**How do you find energy when given voltage?**

In summary, the relationship between potential difference (or voltage) and electrical potential energy is given by ΔV=ΔPEq Δ V = Δ PE q and ΔPE = qΔV.

### How do you calculate watts from volts and amps?

Obtain Amps from Watts and Volts: Insert the number of Watts (W) and Volts (V) below and click on Calculate to obtain Amps (A). The formula is (W)/(V) =(A). For example, if you have a power of 10W running at 5V, the current is 10W / 5V = 2A. This comes from the equation I = P / V.

**How do you find joules from amps and volts?**

If voltage, (V) equals Joules per Coulombs (V = J/C) and Amperes (I) equals charge (coulombs) per second (A = Q/t), then we can define electrical power (P) as being the totality of these two quantities. This is because electrical power can also equal voltage times amperes, that is: P = V*I.

## How do you find current in a circuit?

If the voltage (V) and resistance (R) of any circuit is given we can use the current formula to calculate the current, i.e., I = V/R (amps).

**How do you find amps with volts and work?**

Volts = Watts / Amps Examples: 2400 Watts / 20 Amps = 120 Volts. 2400 Watts / 10 Amps = 240 Volts.

### How do you calculate amps in a circuit?

Divide the watts of a given electrical item by the total number of volts available from the electric outlet to calculate amperage draw. The amount of current flowing through the wire is measured in amperes, or amps.

**How do you measure voltage in a circuit?**

To measure voltage on an electronic circuit, you don’t have to insert the meter into the circuit. Instead, all you have to do is touch the leads of the multimeter to any two points in the circuit. When you do, the multimeter displays the voltage that exists between those two points.

## How do you calculate the power in an electric circuit?

We’ve seen the formula for determining the power in an electric circuit: by multiplying the voltage in “volts” by the current in “amps” we arrive at an answer in “watts.”. Let’s apply this to a circuit example:

**How do I calculate the number of running Watts my appliance needs?**

Just keep in mind that some electric appliances in your home may not have running watts provided on their data tags. If this is the case, you can estimate the running watts required thanks to the following formula: Watts (W or kW) = Volts (V) x Amps (A) Amps (A) = Watts (W or kW) / Volts (V)

### How do you check the wattage of a 110V appliance?

For all 110V AC household devices you can buy a Kill A Watt meter. Plug it in between your device and a wall. Then use your device like normal (laptop, induction burner, etc) for 24 hours. The Kill a Watt will keep track of the Wh used. It’s better to do this for more than one day to get accurate results.

**How do you determine the voltage of a speaker amplifier?**

If you have the resistance in ohms as well, you have enough information via either of the equations: Now for a speaker you also need to know if that was the peak power rating or the RMS (roughly speaking, average) power. If it is 2W “rms” that means 4 volts rms, or 2.8*4 = 11.2 volts peak-peak, which suggests an amplifier running off 12V DC.