<span>Brake </span>is not included in your
perception time.
<span>To add, the total stopping distance of a vehicle is made up
of 4 components. The human </span>perception time; is how long the driver<span> takes to see the hazard, and the brain realize
it is a hazard requiring an immediate reaction.</span>
Answer:
(a) Final speed of block = 3.2896 m/s
(b) 6.7350 m/s is the speed of the bullet-block center of mass?
Explanation:
Given that:
Mass of bullet (m₁) = 6.20 g
Initial Speed of bullet (u₁) = 929 m/s
Final speed of bullet (v₁) = 478 m/s
Mass of wooden block (m₂) = 850g
Initial speed of block initial (u₂) = 0 m/s
Final speed of block (v₂) = ?
<u>By the law of conservation of momentum as:</u>
<u>m₁×u₁ + m₂×u₂ = m₁×v₁ + m₂×v₂</u>
6.20×929 + 850×0 = 6.20×478 + 850×v₂
Solving for v₂, we get:
<u>v₂ = 3.2896 m/s</u>
Let the V be the speed of the bullet-block center of mass. So,
V = [m₁* u₁]/[m₁ + m₂] (p before collision = p after collision)
= [6.2 *929]/[5.2+850]
<u>V = 6.7350 m/s
</u>
Before i Tell you the answer think about it .
For a lever, the mechanical advantage is the ratio of the lever arms. Since the lever arm of the opener is always greater than that of the output arm, the mechanical advantage is greater than 1.
The unit measurement for sound can be expressed in terms of intensity and in decibels. The intensity of sound is the measure of its power over unit area. The common unit of measurement is in decibels. This is commonly used in measuring the extent of noise. The conversion from intensity to the decibel unit is through logarithmic function. The formula is:
dB = 10 log(I/I0), where I0 is 10^-12 Watts per square meter
Substituting the values to the equation,
84 = 10log(I/10^-12)
I = 0.0002512 W/m2
In scientific notation the intensity is 2.512 x 10^-4 W/m^2.
