Surface Tension is a property of liquids that allows their surface to behave like a stretched elastic membrane (this is why small insects can walk on water).
Formula: Force / Length.
Dimensional Formula: [M¹ L⁰ T⁻²].
SI Unit: N/m.
Cause: Cohesive forces between liquid molecules.
Step 1: The formula for Surface Tension (S or T) is: Surface Tension = Force / Length
Step 2: Write the dimensions of Force and Length:
Step 3: Substitute them into the formula: Surface Tension = [M L T⁻²] / [L] Notice that [L] in the numerator and denominator cancel out.
Final Dimensional Formula: [M¹ L⁰ T⁻²]
The dimensional formula of surface tension is [M L⁰ T⁻²] or simply [M T⁻²].
Because surface tension is Force [M L T⁻²] divided by Length [L]. The 'L' cancels out, leaving [L⁰].
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