what must be the distance between source of sound and mountain to give an echo in 5 seconds ? ,(speed of sound at 0°c=33m\sec

Architects have to consider how sound travels when designing large buildings such as theaters, auditoriums, or museums. Sound in

serious [3.7K]

Answer:

I₂ = 0.04 W / m²

Explanation:

Sound intensity is the power emitted between the unit area

I = W / A

W = I A

sound is a wave that travels in space whereby its energy is distributed on the surface of a sphere

A = 4π r²

we substitute

W = I (4π r²)

the emission power is constant, so the intensity at two different points is

W = I₁ 4π r₁² = I₂ 4π r₂²

so the equation is

I₁ r₁² = I₂ r₂²

In this case the units are not shown in the exercise, suppose that all units are in the SI system

I₂ = $I_1 \ \frac{r_1^2}{r_2^2}$

let's calculate

I₂ = 4 $4 \ \frac{2^2}{20^2}$

I₂ = 0.04 W / m²

5 0

3 years ago

Determine the thrust produced if 1.5 x 10^3 kg of gas exits the combustion chamber each second, with a speed of 4.00 x 10^3 m/s.

ozzi

Answer:

The thrust is $6\times 10^6\ N$

Explanation:

Given that,

Mass of gas, $m=1.5\times 10^3\ kg$

The rate at which the gas is expelling, $\dfrac{dv}{dt}=4\times 10^{3}\ m/s$

We need to find the thrust produced by the gas.

We know that force is equal to the rate of change of momentum. So,

$F=\dfrac{p}{t}$

Also, p = mv

$F=\dfrac{mv}{t}$

So,

$F=1.5\times 10^3\times 4\times 10^3\\\\F=6\times 10^6\ N$

So, the thrust is $6\times 10^6\ N$

3 0

4 years ago

If there is no change in the velocity of the object then it is known to be in ______

irga5000 [103]

OPTION (C) IS CORRECT

ANSWER - UNIFORM MOTION

If there is no change in the velocity of the object then it is known to be in <u>UNIFORM MOTION</u>.

EXPLORE MORE:-

EXAMPLE - A CAR COVERS A DISTANCE OF 15 KM WE'D EVERY 2 HOURS

FOR AN UNIFORM MOTION, ACCELERATION IS ZERO , AS THERE IS NO CHANGE IN VELOCITY....

-THANKS.!!

4 0

2 years ago

The efficiency of a carnot cycle is 1/6. If on reducing the temperature of the sink 75 degree Celsius, the efficiency becomes 1/

svp [43]

Answer:

375 and 450

Explanation:

The computation of the initial and the final temperature is shown below:

In condition 1:

The efficiency of a Carnot cycle is $\frac{1}{6}$

So, the equation is

$\frac{1}{6} = 1 - \frac{T_2}{T_1}$

For condition 2:

Now if the temperature is reduced by 75 degrees So, the efficiency is $\frac{1}{3}$

Therefore the next equation is

$\frac{1}{3} = 1 - \frac{T_2 - 75}{T_1}$

Now solve both the equations

solve equations (1) and (2)

$2(1 - T_2/T_1) = 1 - (T_2 - 75)/T_1\\\\2 - 1 = 2T_2/T_1 - (T_2 - 75)/T_1\\\\ = (T_2 + 75)/T_1T_1 = T_2 + 75\\\Now\ we\ will\ Put\ the\ values\ into\ equation (1)\\\\1/6 = 1 - T_2/(T_2 + 75)\\\\1/6 = (75)/(T_2 + 75)$

T_2 + 450 = 75

T_2 = 375

Now put the T_2 value in any of the above equation

i.e

T_1 = T_2 + 75

T_1 = 375 + 75

= 450

7 0

4 years ago

A person is filling a knee-high bucket with water using a garden hose and holding it such that water discharges from the hose at

Serggg [28]

Answer:

Yes i am agree with this suggestion

Explanation:

Given that we have to assume that there is no any frictional affects.

As we know that when height increases then the discharge level will decreases when discharge level decreases then the time of filling for the bucket will increase.So the bucket will fill faster if the hose lowered until knee level.

Yes i am agree with this suggestion

8 0

3 years ago

what must be the distance between source of sound and mountain to give an echo in 5 seconds ? ,(speed of sound at 0°c=33m\sec​

what must be the distance between source of sound and mountain to give an echo in 5 seconds ? ,(speed of sound at 0°c=33m\sec