Physics

Inclined Plane Calculator

Find what happens to a block on a ramp.

Your numbers

Your results

Force down the slope (N)
Force down the slope (N)
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Normal force (N)
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Maximum friction (N)
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Acceleration down the slope (m/s²)
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Result
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Inclined Plane Calculator by TheCalcTools

How the Inclined Plane Calculator works

Enter the mass, the slope angle and the friction coefficient.

Gravity splits into a part along the slope and a part pressing into it.

The block slides if the downslope part exceeds the maximum friction.

The formula

F∥ = m g sin θN = m g cos θ

Worked example

Using the default values shown in the calculator:

Mass (kg)20
Slope angle (°)30
Friction coefficient0.2
  1. Force down the slope = 20 × 9.80665 × sin 30° = 98.07 N.
  2. Maximum friction = 0.2 × 169.86 = 33.97 N.
  3. The block accelerates at 3.20 m/s².

Result:

Force down the slope (N)98.07
Normal force (N)169.86
Maximum friction (N)33.97
Acceleration down the slope (m/s²)3.205
ResultSlides down

Frequently asked questions

At what angle does a block start to slide?

When tan θ exceeds the friction coefficient: θ = arctan μ. For μ = 0.2 that is about 11.3°.

Does mass affect the acceleration?

No. Mass cancels out, so acceleration depends only on the angle and friction.

Sources and further reading

More in Physics · All calculators

This calculator gives estimates for information only. Check important results independently before you rely on them. See our disclaimer.