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Single conversion
To convert from Watt-second (Ws) to Watt-hour (Wh), use the following formula:
Let's convert 5 Watt-second (Ws) to Watt-hour (Wh).
Using the formula:
Therefore, 5 Watt-second (Ws) is equal to Watt-hour (Wh).
Here are some quick reference conversions from Watt-second (Ws) to Watt-hour (Wh):
| Watt-seconds | Watt-hours |
|---|---|
| 0.000001 Ws | Wh |
| 0.001 Ws | Wh |
| 0.1 Ws | Wh |
| 1 Ws | Wh |
| 2 Ws | Wh |
| 3 Ws | Wh |
| 4 Ws | Wh |
| 5 Ws | Wh |
| 6 Ws | Wh |
| 7 Ws | Wh |
| 8 Ws | Wh |
| 9 Ws | Wh |
| 10 Ws | Wh |
| 20 Ws | Wh |
| 30 Ws | Wh |
| 40 Ws | Wh |
| 50 Ws | Wh |
| 100 Ws | Wh |
| 1000 Ws | Wh |
| 10000 Ws | Wh |
For all Energy converters, choose units using the From/To dropdowns above.
A Watt-second (Ws) is a unit of energy in the International System of Units (SI), equal to exactly one Joule (J).
It is a fundamental measurement used to quantify energy transfer, especially in fields like physics and photography.
The relationship is simple: one Watt-second is precisely equal to one Joule.
This 1:1 equivalence means the two units are entirely interchangeable. So, if you have 100 Ws of energy, you also have 100 J of energy.
This makes it a straightforward and reliable unit for any precise energy calculation.
In photography, the Watt-second is the standard for measuring the maximum energy output of a studio strobe or electronic camera flash.
Essentially, a higher Watt-second rating means a more powerful flash.
For example, a 500 Ws strobe has more flash power than a 200 Ws unit, allowing it to produce a much brighter burst of light.
This extra power is crucial for illuminating larger scenes or overpowering ambient light, like bright sunshine.
The name "Watt-second" perfectly describes its own formula.
It is the amount of energy used when one Watt of power is applied for exactly one second.
This gives us the fundamental equation for energy transfer:
Energy (Ws) = Power (W) × Time (s)
To sum up, while the Watt-second is a universal unit of energy equivalent to a Joule, its most common practical use is in photography.
When choosing a studio strobe or camera flash, a higher Ws rating gives you more lighting power, offering greater creative control over your shots.
Ever looked at the back of a battery pack and felt confused by the numbers? You're not alone!
One of the most important measurements you'll see is the Watt-hour (Wh).
Think of it as the fuel gauge for your electronic devices. This simple guide will break down precisely what a Wh is and why it matters.
A Watt-hour (Wh) is a unit that measures energy. Specifically, it tells you how much energy a device uses over a specific period.
The concept is simple: one Watt-hour is the amount of energy consumed when one watt of power is used for precisely one hour.
A helpful analogy is a car's gas tank. The Watt-hour rating on a battery is like the size of the tank—it tells you the total amount of energy it can store.
The power your device draws (measured in Watts) is like how fast you're driving and using up that gas.
A battery with a higher Wh rating holds more energy and can power your device for longer, just like a larger gas tank lets you drive farther.
You'll find Wh ratings on many of the rechargeable devices you use daily. It's a key indicator of battery capacity and runtime. Some common examples include:
The Watt-hour is directly related to the joule (J), which is the standard scientific unit for energy. The conversion is straightforward:
This is because a watt is defined as one joule per second, and there are 3,600 seconds in an hour (60 seconds × 60 minutes).
A kilowatt-hour (kWh) is simply 1,000 Watt-hours. The prefix "kilo-" means one thousand.
You're probably most familiar with kWh from your home electricity bill. Utility companies use this larger unit to measure your household's monthly energy consumption.
So, when you see that you used 500 kWh last month, it means you used 500,000 Watt-hours of energy.