Using the following samples below, elaborate on the practical uses of concave and convex mirrors. Write your answer on a separate sheet of paper.
1. Car rear view mirror
2. Security
3. Street light reflectors
4. Shaving facial hair
5. Car light

Convex mirror is curved in the outward direction and concave mirror in the inward direction.

Explanation:

1. Car rear view mirror: It is a convex mirror which gives the indication of large field of view and it allows the driver to view the traffic behind the car.

2. Security: The reflective bulge surfaces of the convex mirrors reflect the light outwards and provides an expanded field of view of the entire view of shops and other places useful for security.

3. Street light reflectors: They use convex mirrors because they are able to spread the light over the wider area.

4. Shaving facial hair: Concave mirror is used in shaving facial hair. It gives a bigger view of face when it is at the position of pole and focal point of the mirror.

5. Car light: It uses concave mirror because of the converging power it can focus more light rays at a particular point.

number of molecules / avogadro's number * molecule molecular = mass

explanation:

we define a gram-molecular weight as the mass of one mole of any element or compound. a mole contains avogadro's number of units (molecules) –  

6.022

x

10

23

. so, dividing the number of molecules by avogadro's number gives us the number of moles. multiplying that by the molecular weight gives us the mass. from the periodic table we find the gram-molecular weight of u to be238 and of f to be19. so,  

u

f

6

will have a gram-molecular weight of 352g.

a saline water is fed to a reverse osmosis unit at flow rate o rotameter connected to reject (retentate) line reads 8 installed in reject and permeate line reads 15.2 milli siemens/cm and 300 micro siemens/com respectively.