Difference Between Tension and Compression

Main Difference – Tension vs. Compression

Tension and compression refer to forces that attempt to deform an object. The main difference between tension and compression is that tension refers to forces that attempt to elongate a body, whereas compression refers to forces that attempt to shorten the body.

What is Tension

Tension refers to forces that attempt to elongate a body. Whenever you hang an object from a string, for example, the object’s weight pulls on the string, attempting to elongate it. We call the force that is trying to stretch the string “tension”. Due to tension, the molecules that make up the string are forced to move away from their equilibrium positions. The molecules attempt to move back towards their equilibrium position, and in doing so they pull back on the objects that attempt to elongate them. If the forces balance out, then the system comes to an equilibrium, although the string is still under tension and may be elongated beyond its original length.

The weight of an object hanging from a thread exerts a tension on the thread.

When you play tug-of-war, the rope is under tension.

The tension per unit area (the area referred to here is the cross-sectional area, which is at right angles to the force) is often referred to as tensile stress. The term tensile strain refers to the increase in length divided by the original length of the body.

What is Compression

Compression refers to forces that attempt to shorten an object. For example, if you push down on a spring you are exerting a compressive force on it.  If compressive forces act along one direction, the compression is called uniaxial. If the compressive forces act along two or three directions, they are termed biaxial and triaxial compression respectively.

Different types of Tension

The compressive force per unit area (once again, we refer to the cross-sectional area here) of the object is called compressive stress. The ratio of the reduction in length divided by the original length is referred to as the compressive strain.

Bending

When objects bend, they are under compression and tension at the same time. For instance, consider the I-beam shown below:

When objects bend, a part of the object is under tension while another part is under compression.

The top of the beam is under compression while the bottom of the beam is under tension. The line running along the centre of the beam is not under tension or compression. The top and bottom of the I-beam are made thicker (giving it the “I” shape) because these are the regions that experience the most force. Since stress is the force per unit area, having a large surface area allows for the stress on the ends of the beam to be reduced.

Difference Between Tension and Compression

Effects of Force

Tension is a force that attempts to elongate an object.

Compression is a force that attempts to shorten an object.

Image Courtesy:

“Tug of War!” by Jason Eppink (Own work) [], via

“Benging an I-beam” by Avenafatua (Own work) [Public Domain], via

Related pages

difference between a condo and an apartmentdifference between psychologist and psychiatrist salarybig english mastiffswhy is enjambment used in poetryunits of reactanceimportance of paralanguagewhat is the difference between enantiomers and diastereomersdifference between poetry and prosestructure of a vacuole1metric ton tondicot stem definitiondefinition of common and proper nounswhat is the meaning of pure substanceelk vs cariboudefine groanalkynes chemical propertieswhere to buy guar gum and xanthan gumbelgian malinois sizedifference between nucleotide and nucleosideidiom and proverbsrhythm and rhyme definitiondifferentiate between absorption and assimilationwhere are the alkali earth metals on the periodic tablewhat is difference between adjective and adverbs s of hyperglycemia and hypoglycemiaisotonic definition chemistrydifference between electrostatic and gravitational forcekinds of nouns and exampleswhat is leukodermaedible eatabledefine thermoplastic polymerwhat is enjabmentfunctions of microfilamentspleurisy with pneumoniagrana in chloroplastis basil ediblesrso4 compound namedefine double entendresshark a mammal or fishmeaning of smoocheswhat are the uses of vernier caliperdifference between thalassemia and iron deficiency anemiasoliloquy vs monologuedifference between meningitis and encephalitisjuxtaposing definitioninnovation versus inventionaffirmative sentences exampleseukaryotic and prokaryotic comparisonsingapore airport gst refundwhat is alliteration in poemsmetaphor and allegorysushi vs makidifference between aliphatic and aromaticjuxtaposition definition and examplesmoaning groaningdefine de jurebewildered dictionarytime difference between est and pstdefine enthalpy and entropywhat is the plural for alumnisore or soarwhat is the relationship between stereotyping and prejudicezoospores in fungiteeth of herbivoreshansel and gretel short summarywhat is the difference between osteoarthritis and rheumatoidarchaebacteria classification examplessardonic expressiondifference between hurricane and cyclone and tornadowhat is difference between induction motor and synchronous motorwarm blooded means