Understanding Units of Force
In physics, force is a fundamental concept defined as an interaction that causes an object to change its velocity, direction, or shape. The unit of force in the International System of Units (SI) is the Newton (N). However, there are several other units used in different contexts, one of which is the dyne.
What is a Dyne?
- The dyne is a unit of force in the centimeter-gram-second (CGS) system of units.
- It is defined as the force required to accelerate a mass of one gram at a rate of one centimeter per second squared.
- Mathematically, 1 dyne = 1 g·cm/s².
Comparison with Other Units
- Poise: This is a unit of dynamic viscosity, not force. It measures the resistance of a fluid to flow.
- Barye: This is a unit of pressure in the CGS system, equivalent to 0.1 pascal, not a force unit.
- Calorie: A unit of energy, specifically the amount of energy needed to raise the temperature of one gram of water by one degree Celsius.
Conclusion
Among the options provided, the correct unit of force is:
- Dyne (Option D)
This distinction is crucial in physics, ensuring clarity when discussing forces and their effects in various scenarios. Understanding different units helps in converting and applying them in real-world calculations effectively.