Answer:
Photosynthesis
Explanation:
Studies about the time period of oxygen accumulation suggests that free oxygen was first produced by prokaryotic and then later by eukaryotic organisms in the ocean. These organisms carried out photosynthesis more efficiently, producing oxygen as a waste product.
The organism mainly responsible for this is known as cyanobacteria, or blue-green algae. These microbes conduct photosynthesis: using sunshine, water and carbon dioxide to produce carbohydrates and, oxygen.
Answer:
7.5Watts
Explanation:
Given parameters:
Force of lift = 25N
Height = 3.6m
Time = 12s
Unknown:
Power output = ?
Solution:
Power is the rate at which work is done ;
Power =
Power =
= 7.5Watts
In the above problem, we need to find mass of the second child, so that the Center of Mass remains at the origin( pivot).
CM= m1r1+m2r2/m1+m2
0= 20*-2+16*r2/20+16
r2= 40/16
r2= +2.5 m