Answer:
30 seconds ahead.
Explanation:
Its about 90% of the decisions which are made by someone while driving based on what they see. The vision must be good to make the decision accurately and timely before reacting to the environment.
Line of sight is define as the view which you can see without any obstruction. The best condition of proper line of sight is that someone is needed to see in all direction front, behind, left and right.
To establish the clean line of sight the person should search the traffic environment about 30 seconds ahead.
So, I’m assuming that we’re treating light as a propagating wave.
Amplitude measures the amount of energy transported by a wave, thus amplitude squared is directly proportional to the light’s energy. The higher the amplitude, the higher the energy.
Energy is also directly proportional to the frequency of a wave, the higher the frequency, the higher the energy.
I took my second answer from the formula below:
E=cf
Answer:
p2 = 9.8×10^4 Pa
Explanation:
Total pressure is constant and PT = P = 1/2×ρ×v^2
So p1 + 1/2×ρ×(v1)^2 = p2 + 1/2×ρ×(v2)^2
from continuity we have ρ×A1×v1 = ρ×A2×v2
v2 = v1×A1/A2
and
r2 = 2×r1
then:
A2 = 4×A1
so,
v2 = (v1)/4
then:
p2 = p1 + 1/2×ρ×(v1)^2 - 1/2×ρ×(v2)^2 = p1 + 1/2×ρ×(v1)^2 - 1/2×ρ×(v1/4)^2
p2 = 3.0×10^4 Pa + 1/2×(1000 kg/m^3)×(12m/s)^2 - 1/2×(1000kg/m^3)×(12^2/16)
= 9.75×10^4 Pa
= 9.8×10^4 Pa
Therefore, the pressure in the wider section is 9.8×10^4 Pa
