Soru
[3] A 25 kg chair initially at rest on a horizontal floor requires a 165 N horizontal force to set it in motion. Once the chair is in motion, a 127 N horizontal force keeps it moving at a constant velocity. a. Find the coefficient of static friction between the chair and the floor. b. Find the coefficient of kinetic friction between the chair and the floor.
Çözüm
3.5
(265 Oylar)
Yaşar
Usta · 5 yıl öğretmeni
Uzman doğrulaması
Cevap
a. The coefficient of static friction (
) is approximately 0.67.b. The coefficient of kinetic friction (
) is approximately 0.51.
Daha Fazla
## Step 1The problem involves the concepts of static and kinetic friction. The force required to set the chair in motion is the force of static friction, while the force required to keep the chair moving at a constant velocity is the force of kinetic friction.## Step 2The force of static friction (
) is given by the formula:###
where
is the coefficient of static friction and
is the normal force. In this case, the normal force is equal to the weight of the chair, which is the product of the mass of the chair and the acceleration due to gravity (
).## Step 3The force of kinetic friction (
) is given by the formula:###
where
is the coefficient of kinetic friction.## Step 4We can rearrange the formulas to solve for the coefficients of friction:###
###
## Step 5Substituting the given values into the formulas, we get:###
###