Answer:
Explanation:
Let the intensity of the noise be represented by I
Given that
40dB = 10 log 10 ( I /I•) ........ 1
I• is the lowest or threshold intensity of sound made.
I represents the intensity of the sound/ noise
The intensity of noise of 1000flies will be
β = 10 log 10 (1000I/I•)
Open up the bracket
β = 10 log 10(1000)+ 10 log 10(I/I•)
10 log 10(10^3)+10 log 10(I/I•)
3×10(10 log 10) +10 log 10(I/I•)
Recall, 10 log 10 = 1
30×1 + 10 log 10(I/I•).........2
Put equation 1 into 2
β =30+40
= 70db
Answers:
a) 10 m
b) time=1.6 s, frquency=0.625 Hz
c) 6.25 m/s
Explanation:
a) If there is a crest at each dock and another three crests between the two docks, and the wavelength 
is the distance between to crests; this means we have 
in 
:
Clearing :
b) This part can be solved by a Rule of Three:
If 10 waves ---- 16 s
1 wave ----- 
Then:
This is the period of the wave
On the other hand, the frequency 
of the wave has an inverse relation with its period :
This is the frequency of the wave
c) The speed 
of a wave is given by the following equation:
Finally:
Answer: W = 
J
Explanation: Since the potassium ion is at the outside membrane of a cell and the potential here is lower than the potential inside the cell, the transport will need work to happen.
The work to transport an ion from a lower potential side to a higher potential side is calculated by
q is charge;
ΔV is the potential difference;
Potassium ion has +1 charge, which means:
p = 
C
To determine work in joules, potential has to be in Volts, so:
Then, work is
To move a potassium ion from the exterior to the interior of the cell, it is required J of energy.
Answer:
W = 9.93 10² N
Explanation:
To solve this exercise we must use the concept of density
ρ = m / V
the tabulated density of copper is rho = 8966 kg / m³
let's find the volume of the cylindrical tube
V = A L
V = π (R_ext ² - R_int ²) L
let's calculate
V = π (4² - 2²) 10⁻⁴ 3
V = 1.13 10⁻² m³
m = ρ V
m = 8966 1.13 10⁻²
m = 1.01 10² kg
the weight of the tube
W = mg
W = 1.01 10² 9.8
W = 9.93 10² N
Answer:
Explanation:
Ok so first: the evaporation part, the sun starts to get warmer I ( the water droplet) rises up to the sky to start my evaporation cycle
Condensation: part: when I am in the air I change into a gas and then I change back into a liquid and gather my friends and make a cloud
Precipitation: as it gets to crowded, we can’t hold it anymore, when I cool down I like to sky dive with my cousins, snow, rain, sleet, hail which is called precipitation.
Then finally we land on the ground, we run down hills, and run into lakes surface runoff happens when there’s too many of us so some of us can’t be rain. Infiltration: when some of us soak into the ground cause we can’t make it into the streams and oceans. Ok I can’t help much more cause I’m super busy but if you need more help just message me and I can help thx ! Hope I helped Atleast a bit for you to understand more
