Answer: vl = 2.75 m/s vt = 1.5 m/s
Explanation:
If we assume that no external forces act during the collision, total momentum must be conserved.
If both cars are identical and also the drivers have the same mass, we can write the following:
m (vi1 + vi2) = m (vf1 + vf2) (1)
The sum of the initial speeds must be equal to the sum of the final ones.
If we are told that kinetic energy must be conserved also, simplifying, we can write:
vi1² + vi2² = vf1² + vf2² (2)
The only condition that satisfies (1) and (2) simultaneously is the one in which both masses exchange speeds, so we can write:
vf1 = vi2 and vf2 = vi1
If we call v1 to the speed of the leading car, and v2 to the trailing one, we can finally put the following:
vf1 = 2.75 m/s vf2 = 1.5 m/s
<span>there is no horizontal displacement if he went straight up
straight up means vertical, so his vertical displacment is 20 m</span>
Answer:
A major problem in all survey research is that respondents are almost always self-selected. Not everyone who receives a survey is likely to answer it, no matter how many times they are reminded or what incentives are offered.
Explanation:
<em><u>DISADVANTAGES</u></em>
Respondents may not feel encouraged to provide accurate, honest answers.
Respondents may not feel comfortable providing answers that present themselves in a unfavorable manner.
Respondents may not be fully aware of their reasons for any given answer because of lack of memory on the subject, or even boredom.
HAVE A GOOD DAY!
Answer:
Part A
The intensity is 
Part B
The intensity is 
Explanation:
From the question we are told that
The intensity of the light detected by first eye is 
Now at initial state according the question the light ray is perpendicular to the eye so it means that it is at 90° the eye
Now the first question is to obtain the intensity the first eye (the first in this case is the one focused on the light )would detect when the head is rotated by 20° its previous orientation
This is mathematically evaluated as
Now the second question is to obtain the intensity the first eye (the first eye in this case is the one that is not focused on the light )would detect when the head is rotated by 20° its previous orientation
Now in this case the angle between the eye and the light is 90-20 = 70°
So
