All categories

3 years ago

If you are sitting 8.20 m from a

Physics

1 answer:

Elanso [62]3 years ago

8 0

Answer:

Explanation:

There are a lot of assumptions needed for the calculation:

first is the speaker is a point source

second the speaker is 100% efficient in its output

third the sound output propagates as a sphere

Intensity = Power / Surface Area

= 70 / (4*pi*8.20^2)

= 0.082W/m^2

Converting into dB:

= 10*log ( Intensity / (1*10^-12))

= 10*log(0.0828/ (1*10^-12))

= 109 dB

You might be interested in

Semiconductors are materials that conduct electric current better than insulators but not as well as conductors.Semiconductors a

Lina20 [59]

Yes ! it is absolutely true.

3 0

3 years ago

An ac series circuit has an impedance of 60 Ohm and

Iteru [2.4K]

Answer:

Power factor of the AC series circuit is $cos\phi=0.5$

Explanation:

It is given that,

Impedance of the AC series circuit, Z = 60 ohms

Resistance of the AC series circuit, R = 30 ohms

We need to find the power factor of the circuit. It is given by :

$cos\phi=\dfrac{R}{Z}$

$cos\phi=\dfrac{30}{60}$

$cos\phi=\dfrac{1}{2}$

$cos\phi=0.5$

So, the power factor of the ac series circuit is $cos\phi=0.5$ . Hence, this is the required solution.

6 0

3 years ago

Explain the following observations:

Deffense [45]

Answer and Explanation:

a. An oxygen-filled balloon is not able to float in the air, because the oxygen inside the balloon is of the same density, that is, the same "weight" as the oxygen outside the balloon and present in the atmosphere. The balloon can only float if the gas inside it is less dense than atmospheric oxygen. Helium gas is less dense than atmospheric gas, so if a balloon is filled with helium gas, that balloon will be able to float because of the difference in density.

b. The ship is able to float in the water because its steel construction is hollow and full of air. This makes the average density of this ship less than the density of water, which makes the ship lighter than water and for this reason, this ship is able to float. In addition, the ship is partially immersed, allowing the weight of the ship on the water to counteract the buoyant force that the water promotes on the ship. Weight and buoyant are two opposing forces that keep the ship afloat.

6 0

3 years ago

This diagram shows a heating curve for water.

Bess [88]

Answer:

it is B

Explanation:

Because I agree with her and also got 100

6 0

3 years ago

Consider a father pushing a child on a playground merry-go-round. The system has a moment of inertia of 84.4 kg.m^2. The father

Sophie [7]