Normal Force Calculator

Calculate normal force, weight force and the corresponding angle. The weight force is the force that pulls a body downwards, or more precisely towards the center of the earth, at least as long as we are on earth. The normal force, on the other hand, acts perpendicularly on the surface on which the body rests. If the surface is flat, then the normal force and the weight force are equal. If the surface is inclined, the normal force is calculated as the weight force multiplied by the cosine of the angle of inclination.

Please enter two values, the third value will be calculated. This calculation is only defined for an angle between 0 and 90 degrees, although other angles can also be specified. Instead of newton, the unit can also be millinewton or kilonewton, for example, as long as it is the same for both forces.

Examples: with a weight of 100 newtons and an angle of 20 degrees, the normal force is about 17.36 newtons. At 45 degrees it is still 70.71 newtons, which is 100 newtons divided by the square root of 2, corresponding to the calculation of the cosine.

The normal force is needed, for example, to calculate friction using the coefficient of friction. Sometimes you read instead of the normal force F_N or, in connection with this, the normal component of the weight force F_GN. Strictly speaking, these two forces have the same absolute value, but are directed against each other. The normal component of the weight force pulls downwards perpendicular to the plane, the normal force is directed oppositely and can be interpreted as the pressure of the plane on the body above it. Although both forces are directed in opposite directions, for practical calculation reasons they have the same sign and therefore the same value.