1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Tju [1.3M]
3 years ago
8

Two people are talking at a distance of 3.0 m from where you are, and

Physics
1 answer:
tigry1 [53]3 years ago
5 0

Answer:

The sound intensity that the other student measure, I₂ is expected to be;

A) 6.2 × 10⁻⁸ W/m²

Explanation:

The measure of sound intensity is given by the following formula;

I = \dfrac{P}{4 \cdot \pi \cdot R^2}

\dfrac{I_2}{I_1} = \dfrac{R_1^2}{R_2^2}

Where;

I = The intensity

R = The radius

P = The power of the sound

Whereby we have;

The distance of the two people talking, R₁ = 3.0 m

The measure of the sound intensity, I₁ = 1.1 × 10⁻⁷ W/m² (from an online source)

The distance of the other student from the two people talking, R₂ = 4.0 m

Therefore, the estimate of the sound intensity, I₂, is given as follows;

{I_2} = \dfrac{R_1^2}{R_2^2} \times {I_1}

{I_2} = \dfrac{(3.0 \, m)^2}{(4.0 \, m)^2} \times 1.1 \times 10^{-7} \ W/m^2 = 6.1875 \times 10^{-8} \ W/m^2

I₂ = 6.1875 × 10⁻⁸ W/m²

∴ The sound intensity that the other student measure, I₂ ≈ 6.2 × 10⁻⁸ W/m²

You might be interested in
Water is flowing from a garden hose. A child places his thumb to cover most of those outlet, causing a thin jet of high speed wa
Oxana [17]

Answer: maximum height= 40.8m

Explanation: shown in the attachment.

Goodluck

3 0
2 years ago
A swimmer is capable of swimming 0.42 m/s in still water. part a if she aims her body directly across a 66-m-wide river whose cu
satela [25.4K]
<span>If the swimmer is swimming perpendicular to the current, it will take her 66m / 0.42 m/s = 157.14 seconds to cross the river. At the same time, the current will be taking her downstream at a rate of 0.32 m/s. So, when she reaches the opposite bank, her total downstream distance traveled will have been 0.32*157.14 = 50.28 meters.</span>
3 0
3 years ago
A 4.00-m-long, 470 kg steel beam extends horizontally from the point where it has been bolted to the framework of a new building
adell [148]

Answer:

12164.4 Nm

Explanation:

CHECK THE ATTACHMENT

Given values are;

m1= 470 kg

x= 4m

m2= 75kg

Cm = center of mass

g= acceleration due to gravity= 9.82 m/s^2

The distance of centre of mass is x/2

Center of mass(1) = x/2

But x= 4 m

Then substitute, we have,

Center of mass(1) = 4/2 = 2m

We can find the total torque, through the summation of moments that comes from both the man and the beam.

τ = τ(1) + τ(2)

But

τ(1)= ( Center of m1 × m1 × g)= (2× 470× 9.81)

= 9221.4Nm

τ(2)= X * m2 * g = ( 4× 75 × 9.81)= 2943Nm

τ = τ(1) + τ(2)

= 9221.4Nm + 2943Nm

= 12164.4 Nm

Hence, the magnitude of the torque about the point where the beam is bolted into place is 12164.4 Nm

6 0
2 years ago
A 20-kilogram child is riding on a 10-kg sled over a frictionless icy surface at 8.0 meters per second. Calculate the kinetic en
Veseljchak [2.6K]

Answer:

K = 960 J

Explanation:

Given that,

Mass of a child = 20 kg

Mass of a sled = 10 kg

Speed of child on sled = 8 m/s

We need to find the kinetic energy of the sled with the child.

The total mass of child and the sled = 20 kg + 10 kg

= 30 kg

The formula for the kinetic energy of an object is given by :

K=\dfrac{1}{2}mv^2\\\\K=\dfrac{1}{2}\times 30\times (8)^2\\\\K=960\ J

Hence, the kinetic energy of the sled with the child is 960 J.

6 0
2 years ago
Radiation in the ultraviolet region of the electromagnetic spectrum is quite energetic. It is this radiation that causes dyes to
N76 [4]

The  energy of photon in kJ/mol is 329kJ/mol.

Wavelength of radiation is 370nm. The frequency of given wavelength is

            ν = c / λ

            ν = 3×10^8 / 370×10^-9

            ν = 8.11 × 10^14 s^-1

      Now the energy of photon is:

             E = hν

             E = 6.63×10^-34  J.s/photon × 8.11×10^14s^-1

             E = 5.41× 10^-19  J/photon

         To find in mole

              E = 5.41× 10^-19 × 6.022×10^23

               E = 3.29 ×10^ 5 J/mol

   So, the energy of mole of photon is equal to 329 kJ/mol.

        Learn more about radiation here:

                brainly.com/question/18650102

                     #SPJ4  

5 0
1 year ago
Other questions:
  • What is friction and how does it affect objects in motion?
    8·2 answers
  • Newton's first law of motion states that an object remains at rest unless a(n) ____ force acts on it. a. balanced c. gravitation
    8·2 answers
  • When you apply a horizontal force of 76 N to a block, the block moves across the floor at a constant speed ().When you apply a f
    11·1 answer
  • Limestone is an example of
    14·1 answer
  • Which of the following is a nonrenewable resource? a. hydropower b. biomass c. geothermal power d. coal
    7·2 answers
  • *PLEASE HELP*
    15·2 answers
  • The area of a piston of a force pump is 8 X 10⁴m². What force must be
    6·1 answer
  • a effort of 100n can raise a load of 2000n in a hydraulic press. calculate the cross-sectional area of a small piston in it. The
    5·1 answer
  • A pendulum with a length of 1 meter is released from an initial angle of 15.0° after 1000s its amplitude has been reduced by fri
    6·1 answer
  • Nature of components of mixture should be known to separate the mixture why?​
    10·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!