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To convert from Kilocalorie (kcal) to Watt-second (Ws), use the following formula:
With is the ratio between the base units Joule (J) and calorie (cal).
Let's convert 5 Kilocalorie (kcal) to Watt-second (Ws).
Using the formula:
Therefore, 5 Kilocalorie (kcal) is equal to Watt-second (Ws).
Here are some quick reference conversions from Kilocalorie (kcal) to Watt-second (Ws):
| Kilocalories | Watt-seconds |
|---|---|
| 0.000001 kcal | Ws |
| 0.001 kcal | Ws |
| 0.1 kcal | Ws |
| 1 kcal | Ws |
| 2 kcal | Ws |
| 3 kcal | Ws |
| 4 kcal | Ws |
| 5 kcal | Ws |
| 6 kcal | Ws |
| 7 kcal | Ws |
| 8 kcal | Ws |
| 9 kcal | Ws |
| 10 kcal | Ws |
| 20 kcal | Ws |
| 30 kcal | Ws |
| 40 kcal | Ws |
| 50 kcal | Ws |
| 100 kcal | Ws |
| 1000 kcal | Ws |
| 10000 kcal | Ws |
For all Energy converters, choose units using the From/To dropdowns above.
A kilocalorie (kcal) is a unit used to measure energy.
Just as a kilometer is 1,000 meters, one kilocalorie is equal to 1,000 small calories (cal).
It's the most common unit for discussing the energy content of food.
Have you ever noticed the word "Calories" on a food label? What you're actually seeing is a kilocalorie (kcal).
Here's the simple breakdown:
Essentially, in the world of nutrition, the terms Calorie and kilocalorie are used interchangeably.
The "small calorie" (cal) is a much smaller unit and is primarily used in science labs.
Scientifically, a kilocalorie is the amount of energy needed to heat one kilogram of water by one degree Celsius.
This precise measurement allows scientists to determine how much energy your body can get from the macronutrients in your food, such as:
When a food label says a serving has 100 Calories, it means that's the amount of energy your body can use from it.
The kilocalorie isn't just for food!
As a fundamental unit of energy, it's also used in fields like physics and chemistry to measure energy in chemical reactions and heat transfer.
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.