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2 years ago

15

The sound level measured in a room by a person watching a movie on a home theater system varies from 40 dB during a quiet part t

o 80 dB during a loud part. Approximately how many times louder is the latter sound

1 answer:

UNO [17]2 years ago

7 0

Answer:

$\alpha=-3.01dB$

Explanation:

From the question we are told that:

Sound level intensity

$\triangle I=40dB-80dB$

Generally the equation for intensity level is mathematically given by

$\alpha=10log_{10}(I/I_x)dB$

Where

I= Intensity measured

$I_x=Threshold\ of\ audibility$

$I_x= 10-12 W / m2$

$\alpha= 10 log10 \frac{I_1}{I_x} - 10 log10 \frac{}I_2{I_x}$

$\alpha= 10 log10 \frac{I_1}{I_2}$

$\alpha=10 log10\frac{40}{80}$

$\alpha=-3.01dB$

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Answer:

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Explanation:

<u>Given the following data;</u>

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Kinetic energy can be defined as an energy possessed by an object or body due to its motion.

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Where,

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M represents mass measured in kilograms.

V represents velocity measured in metres per seconds square.

Substituting into the equation, we have;

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2 years ago

II Force on a tennis ball. The record speed for a tennis ball that is served is 73.14 m/s. During a serve, the ball typically st

AveGali [126]

Answer:

F=248.5W N

Explanation:

Newton's 2nd Law tells us that F=ma. We will use their averages always. The average acceleration the tennis ball experimented is, by definition:

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Since we start counting at 0s and the ball departs from rest, this is just $a=\frac{v}{t}$

So we can write:

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$F=\frac{Wv}{gt}=\frac{v}{gt}W$

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Explanation:

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3 years ago

As a woman walks, her entire weight is momentarily placed on one heel of her high-heeled shoes. Calculate the pressure exerted o

STatiana [176]

Answer:

3335400 N/m² or 483.75889 lb/in²

Explanation:

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When we divide force by area we get pressure

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3 years ago

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The total mass of the cone (m) = Density of the cone × volume of the cone

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center of mass lies at, h' = $\frac{1}{4}\times4=1m$

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