Answer:
μ = 0.33
Equal to 3.2 m/s²
Explanation:
Draw a free body diagram of the block. There are three forces:
Normal force N pushing up.
Weight force mg pulling down.
Friction force Nμ pushing opposite the direction of motion.
Sum of forces in the y direction.
∑F = ma
N − mg = 0
N = mg
Sum of forces in the x direction.
∑F = ma
Nμ = ma
Substitute.
mgμ = ma
μ = a/g
μ = (3.2 m/s²) / (9.8 m/s²)
μ = 0.33
As found earlier, the acceleration is a = gμ. Since g and μ are constant, a is also constant, so it does not change with velocity.
A scientific law is a principle that describes the behavior of a natural phenomenon.
Example: Newton's Laws of Motion
Recall the force applied to a spring and its extension/compression:
F = kΔx
Δx is the change in the spring's length (measured from its original length).
x = 0.7 m
x₀ = 0.4 m
Δx = x-x₀ = 0.7 m - 0.4 m = 0.3 m
F = 23 N
Substitute and solve for k:
23 = k×0.3
<h3>k = 7.67 N/m</h3>