What is a poundal (pdl)?
A poundal (pdl) is a unit of force from the foot-pound-second (FPS) system. It’s the force needed to accelerate a 1-pound mass at 1 foot per second squared (1 ft/s²). You may see it in older physics texts and engineering notes.
What is a dyne (dyn)?
A dyne (dyn) is a unit of force in the centimeter-gram-second (CGS) system. It’s the force needed to accelerate a 1-gram mass at 1 centimeter per second squared (1 cm/s²). Dynes are common in older mechanics problems and some lab work.
How do you convert poundals to dynes?
Use this conversion factor:
- 1 poundal (pdl) = 13,825.495 dynes (dyn)
To convert poundals to dynes, multiply by 13,825.495:
What is the formula for pdl to dyn?
The standard formula is:
If you need the reverse conversion:
Why does 1 poundal equal 13,825.495 dynes?
The poundal is based on feet, pounds, and seconds. The dyne is based on centimeters, grams, and seconds. The conversion comes from changing feet to centimeters and pounds (mass) to grams, while keeping the same acceleration structure in each system.
Is a poundal a unit of force or mass?
A poundal is a unit of force. It’s tied to a 1-pound mass and a 1 ft/s² acceleration, but the result is still force.
Are dynes part of the SI system?
No. The SI unit of force is the newton (N). The dyne is a CGS unit. You may still see dynes in older references or in some niche fields.
How many dynes are in 10 poundals?
Multiply by the conversion factor:
- 10 pdl = 10 × 13,825.495 = 138,254.95 dyn
How do poundals and dynes compare to newtons?
Here are helpful reference points:
- 1 dyne = 1 × 10⁻⁵ newton (N)
- 1 poundal = 0.13825495 N
- 1 poundal = 13,825.495 dyn
These values help when you need to move between CGS, FPS, and SI units.
What are common mistakes when converting pdl to dyn?
A few errors come up often:
- Mixing up force and mass units (pdl is force, not lbm).
- Using pound-force (lbf) instead of poundal (pdl).
- Flipping the operation (dividing when you should multiply).
- Rounding too early and losing accuracy.
Should I round the result when converting to dynes?
Round based on how precise your input is. If your poundal value has two decimal places, don’t report dynes with ten. For most work, 3 to 6 significant figures is enough unless your lab or spec calls for more.