how to calculate frictional resistance
Answers
Answer:
Friction is the resistance to motion of one object moving relative to another. It is not a fundamental force, like gravity or electromagnetism. Instead, scientists believe it is the result of the electromagnetic attraction between charged particles in two touching surfaces
Explanation:
Calculate the force of friction using the formula:
F = μN
Where N is the normal force and μ is the friction coefficient for your materials and whether they’re stationary or moving. The normal force is equal to the weight of the object, so this can also be written:
F = μmg
Where m is the mass of the object and g is the acceleration due to gravity. The friction acts to oppose the motion of the object.
The coefficient depends on the object and the specific situation you’re working with. If the object isn’t already moving across the surface, you use the coefficient of static friction μstatic, but if it is moving you use the coefficient of sliding friction μslide.
Generally, the coefficient of sliding friction is smaller than the coefficient of static friction. In other words, it’s easier to slide something that’s already sliding than to slide something that’s still.
The materials you’re considering also affect the coefficient. For example, if the block of wood from earlier was on a brick surface, the coefficient would be 0.6, but for clean wood it can be anywhere from 0.25 to 0.5. For ice on ice, the static coefficient is 0.1. Again, the sliding coefficient reduces this even more, to 0.03 for ice on ice and 0.2 for wood on wood. Look these up for your surface using an online table (see Resources).