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3 years ago

8

Oil spilled from a ruptured tanker spreads in a circle whose area increases at a constant rate of 5.5 mi2/hr. How rapidly is rad

ius of the spill increasing when the area is 6 mi2?

1 answer:

Travka [436]3 years ago

8 0

<h2>The radius will increase at the rate of 0.64 mi/hr </h2>

Explanation:

The area of a circle can be represented by A = π r² I

Differentiating both sides w.r.t time

$\frac{dA}{dt}$ = 2π r $\frac{dr}{dt}$ II

Dividing II by I , we have

$\frac{dA}{A}$ = 2 x $\frac{dr}{r}$

substituting the values

$\frac{dr}{r}$ = $\frac{5.5}{12}$ = 0.46 mi per unit radius

or dr = 1.4 x 0.46 = 0.64 mi/hr

here 1.4 mi is the radius , when area of circle is 6 mi²

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Explanation:

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2) weight (acting in the downward direction) = mg

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It is known that the weight of electron is far less compared to electric force. Therefore, we can neglect the weight and the above equation will be as follows.

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Which three statements about electromagnetic radiation are true?

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I think that numbers one, three, and four are true

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Sound travels through water at a speed of 1500 m/s. If the frequency of a sound is 1000 Hz, what is the wavelength?

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A cannon with a muzzle speed of 1 000 m/s is used to start an avalanche on a mountain slope. The target is 2 000 m from the cann

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Answer:

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Target height (h) = 800 m

Projection angle ∅ = ?

Horizontal distance = $V_{1x}$ tcos ∅ .......................... Equation 1

where $V_{1x}$ = velocity in the X - direction

t = Time taken

Vertical Distance = y = $V_{1y}$ t - $\frac{1}{2}$ g $t^{2}$ ................... Equation 2

Where $V_{1y}$ = Velocity in the Y- direction

t = Time taken

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Making time (t) subject of the formula in Equation 1

t = d/( $V_{1x}$ cos ∅)

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substituting equation 3 into equation 2

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Vertical Distance = h = sin∅ $\frac{d}{cos o}$ - $\frac{1}{2}$ g $\frac{2}{cos0} ^{2}$

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Applying geometry

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substituting the given parameters

800 = 2000 tan ∅ - 2 (9.81)( $tan^{2} o$ + 1)

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