Answer:
It is an example of negative feedback mechanism
Explanation:
Negative feedback mechanism is the process by which the output of a system, process or mechanism is fed back into the input in order to reduce the error in the system.
In the system described in this question, the reabsorption of water is the output, a feedback signal is sent to the control center, which is the input in order to control the release of the hormone responsible for reabsorption of water into the blood.
It's been a while since I've studied this, but my answers would be:
13. 5730 years. The half-life of a substance is the amount of time it takes for half of it to decay, and, according to the graph, half of the substance remained at 5730 years.
14. 10740 years. According to the graph, only 25% of the carbon remained after 10740 years.
15. 15 atoms. According to the graph, only 12.5% of the carbon remained after 16110 years. 12.5% of 120 atoms is 15 atoms.
16. 1600 atoms. According to the graph, if a sample of carbon is 10740 years old, only 25% of it remains. To find the original amount, multiply the current amount by (100% / 25%), which equals 4. So, 4. 400 atoms * 4 = 1600 atoms is the original amount.
Answer:
a. Speed = 342.5 meters per seconds.
b. Wavelength = 2.0 meters
Explanation:
Given the following data;
Distance = 100m
Time = 292 milliseconds to seconds = 292/1000 = 0.292 seconds
Frequency = 171 Hz
a. To find the speed of sound in air;
Speed = distance/time
Speed = 100/0.292
Speed = 342.5 m/s
b. To find the wavelength;
Wavelength = speed/frequency
Wavelength = 342.5/171
Wavelength = 2.0 m
Answer:162.516 gm
Explanation:
Given
Quartz contains 46.7 % silicon by mass
i.e.Silicon is 46.7 % by mass
Total mass of Quartz m=348 gm
46.7% of 348 gm