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3 years ago

One speaker generates sound waves with amplitude A.

Physics

1 answer:

raketka [301]3 years ago

7 0

Answer:

iv) It is 9x bigger than before

Explanation:

As the amplitudes of the new speakers add directly with the original one, taking into account the phase that they have, the composed amplitude of the sound wave is as follows:

At = A + 4A -2A = 3 A

The intensity of the wave, assuming it propagates evenly in all directions, is constant at a given distance from the source, and can be expressed as follows:

I = P/A

where P= Power of the wave source, A= Area (for a point source, is equal to the surface area of a sphere of radius r, where is r is the distance to the source along a straight line)

For a sinusoidal wave, the power is proportional to the square of the amplitude, so the intensity is proportional to the square of the amplitude also.

If the amplitude changes increasing three times, the change in intensity will be proportional to the square of the change in amplitude, i.e., it will be 9 times bigger.

So, the statement iv) is the right one.

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Britney is aware of the thoughts running through her mind and the emotions triggered by some of those thoughts. She is also awar

Sonbull [250]

Answer:

Consciousness

Explanation:

Obstructionism is the philosophy which dictates that a process needs to be delayed or stopped from occurring.

Transcendence means to achieve a state higher than the previous state.

Hyperkinesis is the condition where a person is unable to concentrate on something and is hyperactive.

Consciousness is the state from which an organism knows their existence and is aware of things that are present externally. Here, Britney is aware of her existence and the existence of other things around her.

Hence, she would be considered to be in a state of Consciousness

3 0

4 years ago

A copper wire has a radius of 3.5 mm. When forces of a certain equal magnitude but opposite directions are applied to the ends o

denpristay [2]

Answer:

The tensile stress on the wire is 550 MPa.

Explanation:

Given;

Radius of copper wire, R = 3.5 mm

extension of the copper wire, e = 5.0×10⁻³ L

L is the original length of the copper wire,

Young's modulus for copper, Y = 11×10¹⁰Pa.

Young's modulus, Y is given as the ratio of tensile stress to tensile strain, measured in the same unit as Young's modulus.

$Y =\frac{Tensile \ stress}{Tensile \ strain} \\\\Tensile \ stress = Y*Tensile \ strain\\\\But, Tensile \ strain = \frac{extension}{original \ Length} = \frac{5.0*10^{-3} L}{L} = 5.0*10^{-3}\\\\Tensile \ stress = 11*10^{10} *5.0*10^{-3} \ = 550*10^6 \ Pa$

Therefore, the tensile stress on the wire is 550 MPa.

8 0

3 years ago

At this output power, how long would it take an 89 kg cyclist (including the mass of his bike) to climb the famed 1100-m-high al

Artemon [7]

In general the route that follows the 1100-m-high alpe d'huez mountain stage takes anywhere from four to six hours in athletes from around the world. A beginner would probably take 8 hours or so. World records were recently broken with a time just under three hours. The most friction for cyclist is the competition itself.

7 0

4 years ago

The combined focal length of two thin lens is 24 cm and the focal length of one converging lens is 8

qwelly [4]

Answer: f = -12 cm

Explanation: Combined lenses is an array of simple lenses with a common axis. The combination is useful for correction of optical aberrations which cannot be corrected by simple lenses.

When two lenses are in contact and are thin, focal lengths are related as:

$\frac{1}{F} =\frac{1}{f_{1}} +\frac{1}{f_{2}}$