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GaryK [48]
3 years ago
15

A spherical balloon is being inflated. Find the rate of increase of the surface area (S = 4Ï€r2) with respect to the radius r wh

en r is each of the following. (Answers in unit ft2/ft)
(a) 1 ft

(b) 3 ft

(c) 6 ft
Physics
1 answer:
erastovalidia [21]3 years ago
8 0

Answer:

A) 8π ft²/ft

B) 24π ft²/ft

C) 48π ft²/ft

Explanation:

Surface area of the spherical balloon is not clear here but it is supposed to be;

S = 4πr²

where:

r is the radius of the spherical balloon

So thus, the rate of change of the surface area of the spherical balloon by its radius will be:

dS/dr = 8πr

A) at r = 1ft;

dS/dr = 8 × π × 1

dS/dr = 8π ft²/ft

B) at r = 3 ft;

dS/dr = 8 × π × 3

dS/dr = 24π ft²/ft

C) at r = 6ft;

dS/dr = 8 × π × 6

dS/dr = 48π ft²/ft

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Data:
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Formula:
V = R*i

Solving:
V = R*i
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\boxed{\boxed{V = 108\:volts}}\end{array}}\qquad\quad\checkmark
6 0
3 years ago
An AC generator consists of eight turns of wire, each of area 0.0775 m2 , and total resistance of 8.53 Ω. The loop rotates in th
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Answer:

44.08 Volt

Explanation:

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3 0
3 years ago
Why will a delivery truck filled with birds sitting on its floor be heavier than a truck with the same birds flying around insid
34kurt

The reason why a delivery truck filled with birds sitting on the floor be heavier than a truck with the same birds flying around is because when the birds are sitting on the floor, they are adding their weight to the truck.

Meanwhile, if the birds are flying around they aren't resting on the truck or touching it, so therefore their weight wouldn't be added to the truck.

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4 0
3 years ago
Sonar is used to determine the speed of an object. A 38.0-kHz signal is sent out, and a 40.0-kHz signal is returned. If the spee
ANEK [815]

Answer:

The velocity is  v  =  8.743 \ m/s

Explanation:

From the question we are told that

    The frequency of the signal sent out  is  f_s  =  38.0 \ kHz  =  38.0 *10^{3} \ Hz

    The frequency of the signal received is  f_r  =  40.0 \ kHz  =  40.0 *10^{3} \ Hz

     The  speed of sound is  v_s  =  341 \ m/s

Generally the frequency of the sound received is  mathematically represented as

         f_r =  f_s  [\frac{v_s  + v}{v_s  - v} ]

where v is the velocity of the object

       =>      40 *10^{3} =  38 *10^{3} *   [\frac{341  + v}{341  - v} ]

       =>      1.05263 = \frac{341+v }{341-v}

       =>   358.94 - 1.05263v  =  341 + v

      =>    17.947 =  2.05263 v

      =>    v  =  8.743 \ m/s

7 0
3 years ago
What is oxygen an example of? a mixture, an element, a compound, or a solution
soldi70 [24.7K]

Answer: element

Explanation:

Couldn't be a compound because contains same type of atoms. Can't be a mixture either because not physically mixed or anything. Isn't a solution ofc because oxygen is a gas.

7 0
3 years ago
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