Difference Between Compression and Tension

Compression vs Tension
 

Tension and compression are two concepts discussed in physics. Tension is a force while compression is a phenomenon. Both these concepts play important parts in fields such as mechanical systems, automobile engineering, heat engines, material science, pendulums and various other fields. It is vital to have a proper understanding in tension and compression in order to excel in such fields. In this article, we are going to discuss what compression and tension are, their definitions, applications of compression and tension, the similarities between compression and tension and finally, the difference between compression and tension.

Tension

Tension is defined as the pulling force exerted by a cable, string, chain or a similar object. There are two types of strings. A weightless string is a hypothetical string with no weight. A real string is a string with a finite amount of weight. These two definitions are important in describing the tension. When an object is pulled by a string, the tension occurs at every point of the string. This is due to the intermolecular attractions. The bonds between the molecules act as small springs, keeping the two molecules from separating. When a force tries to stretch the string, these bonds resist the deformation. This causes a series of balanced force throughout the string. Only the two ends of the string have unbalanced forces. The unbalanced force at the end, at which the initial force is acted, is balanced by the initial force. The unbalanced force at the object’s end acts on the object. In this sense, tension can be considered as a force propagation method. If the string has a weight the string will not be horizontal, thereby the weight of the string must be added to the calculation.

Compression

Compression is the reduction of the volume of a gas, liquid, or a solid due to external forces acting upon it. The compression itself is not a well-defined quantity. It can be taken as the amount of volume reduced or the percentage of the amount of volume reduced. The quantitative measurement of compression is the Young’s modulus for solids and the compressibility factor for gases. Young’s modulus is the ratio of the pressure on the object (stress), to the strain of the object. Since strain is dimensionless, the units of Young’s modulus are equal to the units of pressure, which is Newton per square meter. For gases, the compressibility factor is defined as PV/RT, where P is the pressure, V is the measured volume, R is the universal gas constant, and T is the temperature in Kelvin.

 

What is the difference between Compression and Tension?

• Tension is a force propagation method; compression can be used to transfer force as pressure in hydraulic systems, but a compressive process does not occur.

• Tension is a force, whereas compression is a phenomenon. Tension is only valid in solid strings, but compression can be applied to any material.

• In tension, the force acting on the object is always outward from the object. In compression, the force acting on the object is inward to the object.