Its D because i know that smoke does change very easily and its particles that dissolves in air which was infuenced by the gas. hope this helps man ;)
Answer:
As Per Given Information
20x objective lens was used by specimen
10x ocular lens was also used by him.
we have to find the total magnification.
For calculating the total magnification we 'll simply do multiplication
Total Magnification = 20x × 10x
Total Magnification = 200x
So , the total magnification will be 200x .
Answer:
Explanation:
radius of circle r = 0.9 m.
(a ) In a motion on circular path , work done is zero because force ( centripetal force ) acts perpendicular to displacement .
( b )
Tension in string T = m ω²r
Putting the values
60 = .072 x ω² x 0.9
ω² = 926
ω = 30.4 rad /s
angle made in 20 revolutions θ = 20 x 2π = 126.6 rad
time taken = θ / ω
= 126.6 / 30.4
= 4.16 s .