Assuming it is on a horizontal surface:
friction = μR
R = 20g (g is gravity 9.81)
so Friction = 0.085 x 20g
Work done is force x distance
so Work done = 0.085 x 20g x 28
= 466.956 J
Chemical stimuli are molecules that cause a response at a cellular level primarily through cellular receptors. This happens all the time in nature - cells communicate with one another through chemical messaging. An example is an aroma molecule, such as the scent from a flower. This particular molecule is detected by the olfactory cells (those associated with the sense of smell) in your nose, producing a chemical reaction that ultimately leads to you consciously experiencing the smell.
Answer:
fr = m v₀² / 2 (x₁-x₀)
Explanation:
a) For this exercise we use Newton's second law
X axis
- fr = ma
Y Axis
N-W = 0
N=W
let's look for acceleration with expressions of kinematics
v² = v₀² - 2 a Δx
at the point where stop v = 0
a = v₀² / 2 Δx
let's replace
-fr = m (- v₀² / 2 (x₁-x₀))
fr = m v₀² / 2 (x₁-x₀)
b)they ask for the same
in this case part of rest
v₁² = 0 + 2 a Δx
a = v₁² / 2ΔX
we write Newton's second law
F - fr = m a
fr = F - ma
fr = F - m v₁² / 2Δx
