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:
The height is 6 inches.
Step-by-step explanation:
Area of the square = length of a side squared.
This square has area 6^2 = 36 in^2.
Area of the parallelogram = base * height
= 6h.
As the areas are equal:
6h = 36
h = 36/6 = 6 inches.
Direct variation has this equation:
y = kx
where k is the constant of variation
y = -5 ; x = -15
y = kx
-5 = k(-15)
-5/-15 = k
1/3 = k
Choice D. y = 1/3 x
Answer:
40 units
Step-by-step explanation:
For a square, all the sides are equal and the interior angles are equal and all equal to 90. Hence;
m<BOJ = 90 degrees
m<BOJ = 4x - 6
Equating both to get x;
4x - 6 = 90
4x = 90+6
4x = 96
x = 96/4
x = 24
Since all the sides are equal, hence BO = JO = 2x-8
JO = 2x - 8
Substitute x = 24 into JO
JO = 2(24) - 8
JO = 48 - 8
JO = 40
Hence the measure of JO is 40 units
Answer:
Option 3: 300 phones
Step-by-step explanation:
Given
Phone produces each day: 1000
Number of phones that were checked = 30
Defective phones = 9
So the probability of defective phones will be calculated by dividing the number of defective phones by total number of phones checked.
So, the probability of defective phones
= 9/30
= 0.3 or 30%
So, from 1000 phones the defective phones will be:
1000*0.3
= 300 Phones ..