Answer:
correct option is C) 2.8
Step-by-step explanation:
given data
string vibrates form = 8 loops
in water loop formed = 10 loops
solution
we consider mass of stone = m
string length = l
frequency of tuning = f
volume = v
density of stone = 
case (1)
when 8 loop form with 2 adjacent node is 
so here
..............1
and we know velocity is express as
velocity = frequency × wavelength .....................2
= f × 
here tension = mg
so
= f × ..........................3
and
case (2)
when 8 loop form with 2 adjacent node is
..............4
when block is immersed
equilibrium eq will be
Tenion + force of buoyancy = mg
T + v × × g = mg
and
T = v × - v × × g
from equation 2
f × 
= f × 
.......................5
now we divide eq 5 by the eq 3
solve irt we get
so
relative density 
relative density = 2.78 ≈ 2.8
so correct option is C) 2.8
Answer:
Step-by-step explanation:
Alright, so 3f-g=4 and f+2g=5.
3f-g=4
f+2g=5
Multiplying the first equation by 2 and adding it to the second, we get 7f=13 and by dividing both sides by 7 we get f=13/7. Since f+2g=5, then we can plug 13/7 in for f to get 13/7+2g=5. Next, we subtract 13/7 from both sides to get 2g=3+1/7=22/7 (since 3*7=21 and 21+1=22). DIviding both sides by 2, we get 22/14=g. Plugging that into f/39g, we get (13/7)/(22*39/14)
= (13/7)/(858/14)
= (13/7)*(14/858)
=182/6006
= 91/3003 (by dividing both numbers by 2)
= 13/429 (by dividing both numbers by 7)
= 1/33 (by dividing both numbers by 13)
Answer:
Step-by-step explanation:
cos 43=cos (90-47)=sin 47
