How to Calculate Power to Weight Ratio

Rockets have an enormous power to weight ratio.

The power to weight ratio is a common expression used when discussing the relative power of an engine. Since most engines are attached to vehicles that move, the weight of the vehicle on which the engine is mounted must be included in the calculation of the power to weight ratio. The power to weight ratio is significant because it allows different vehicles to be compared based on the relative power of each.

Things You'll Need

• Pencil
• Paper
• Calculator

Instructions

Find the Power

1. Find the power of the engine or vehicle for which you will be calculating the power to weight ratio.

2. Write down the power in whatever units it is specified.

3. Convert the unit to horsepower, watts or newtons, as per your preference.

Find the Weight

1. Find the weight of the vehicle or engine.

2. Write down the weight. Convert the weight to kilograms, pounds or the unit of your preference.

3. Divide the power by the weight. This is the power to weight ratio as per the units you chose.

Tips & Warnings

• The units can be converted easily once you find the conversion algorithms. Conversion algorithms are available online.

• The completed power to weight ratio is expressed in the units you chose to calculate.

• The power to weight ratio will reflect only the power to weight ratio of the engine alone if you do not find the net weight of the vehicle before calculating.

References

• AjDesigner.com: Horsepower Design Equations and Formulas Calculator