Answer:
A. 6.282
B. 2.03kg
Explanation:
A.
We solve using archimedes principle
L³pwood = L²dwater
We make d subject of the formula
d = Lpwood/pester
= 18x651/1000
= 18x0.651
= 11.718cm
Distance from horizontal top to water level
= 18-11.718
= 6.282cm
B.
When we place lead block
WL + L³pwoodg = L³pwaterg
WL = L³g(Pwater-Pwood)
= 0.18³x9.8(1000-651)
= 19.94N
19.94/9.8
= 2.03kg
The mass m is therefore 2.03kg
Answer:
option (e) is correct.
Explanation:
mass of adult, M = 81 kg
Gravitational Potential energy of adult, U = 2000 J
Let the height raised is h.
U = mass of adult x g x h
2000 = 81 x 9.8 x h
h = 2.52 m
mass of adult, m = 18 kg
height raised, h = 2.52 m
Potential energy of child, U' = m x g x h
U' = 18 x 2.52 x 9.8 = 444.44 J
Thus, option (e) is correct.
DB = 10 log (I/Io)
Where, Io is the reference intensity which is the minimum intensity that human can hear.
That is; Io = 10^-12
Therefore;
dB = 10 log (0.000127/10^-12) =80.79
= 81 dB
Therefore; the correct answer is 81 dB
Solar radiation is the fundamentalenergy driving our climate system, and nearly all climatic and biologicprocesses on Earth are dependent on solar input. Energy from the sun isessential for many processes on Earthincluding warming of the surface, evaporation, photosynthesis and atmospheric circulation.
