Respuesta :
Answer:
a) frictional force = 93.8 N
b) acceleration = 1.29 ms∧-2
Explanation:
The frictional force can be calculated by :
μ k = Fk / N
where:
- μ k = coefficient of kinetic friction = 0.14
- N= normal force or the force perpendicular to the contacting surface
- Weight of the crate, W = mg = (67 × 10) == 670 N
take acceleration due to gravity = 10m/s∧2
The normal force , N = W = 670N ( upward force equals downward force)
Fk = μ k × N
= 0.14 × 670
Fk = 93.8 N
b) To calculate the magnitude of crate's acceleration
F - Fk = ma
where
- Fk = frictional force = 93.8N
- F = horizontal force = 180 N
- m = mass = 67.0 kg
- a = magnitude of acceleration (unknown)
by substituting,
180 - 93.8 = 67a
86.2 = 67a
acceleration, a = (86.2 ÷ 67)
a = 1.29 ms∧-2
