Answer:
The answer is 0.83 seconds.
Explanation:
The formula of free fall is following:

Where g=9.8 m/s^2 and t=2 seconds, the rock takes:

19.6 meters. This is the half distance of the cliff. The whole distance is 39.2 meters. So it takes:

2.83 second to fall down completely. The rock takes the second half of the cliff in 0.83 seconds
Answer:
Concentrating solar power (CSP) plants use mirrors to concentrate the sun's energy to drive traditional steam turbines or engines that create electricity.
Explanation:
The student who did the most work is student 2 with 2500 Joules.
<u>Given the following data:</u>
To determine which of the students did the most work:
Mathematically, the work done by an object is given by the formula;

<u>For </u><u>student 1</u><u>:</u>

Work done = 600 Joules
<u>For </u><u>student 2</u><u>:</u>

Work done = 2500 Joules.
Therefore, the student who did the most work is student 2 with 2500 Joules.
Read more: Read more: brainly.com/question/13818347
Answer:
Final speed of boat + man is 1.66 m/s
Explanation:
As we know that there is no friction on the system or there is no external force on this system
So here we can use momentum conservation here

so we have
m = 85 kg
M = 135 kg
v = 4.30 m/s
now we have


I'm pretty sure the answer is gold