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3 years ago

Express the surface area of a cube as a function of its volume v.

1 answer:

5 0

The surface area of a cube is:

S = 6l², making l the subject:
l = √(S/6)

While the volume is:

V = l³

If we substitute l to get:

V = (√(S/6))³

√(S/6) = ³√V

S/6 = (³√V)²

S = 6(³√V)² ⇒ 6V^(2/3)

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The pickup truck has a changing velocity because the pickup truck

yaroslaw [1]

Answer:

travilng on a curve in the road

Explanation:

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3 years ago

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If a sound waves frequency is 100Hz. what is its period

agasfer [191]

Period = (1/frequency) .

If frequency is 100 per second, then

Period = (1) / (100 per second) = 0.01 second .

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3 years ago

An atom of carbon has a radius of 67.0 pm and the average orbital speed of the electrons in it is about 1.3 x 10⁶ m/s.

adoni [48]

Answer :

The least possible uncertainty in an electron's velocity is, $4.32\times 10^{5}m/s$

The percentage of the average speed is, 33 %

Explanation :

According to the Heisenberg's uncertainty principle,

$\Delta x\times \Delta p=\frac{h}{4\pi}$ ...........(1)

where,

$\Delta x$ = uncertainty in position

$\Delta p$ = uncertainty in momentum

h = Planck's constant

And as we know that the momentum is the product of mass and velocity of an object.

$p=m\times v$

or,

$\Delta p=m\times \Delta v$ .......(2)

Equating 1 and 2, we get:

$\Delta x\times m\times \Delta v=\frac{h}{4\pi}$

$\Delta v=\frac{h}{4\pi \Delta x\times m}$

Given:

m = mass of electron = $9.11\times 10^{-31}kg$

h = Planck's constant = $6.626\times 10^{-34}Js$

radius of atom = $67.0pm=67.0\times 10^{-12}m$ $(1pm=10^{-12}m)$

$\Delta x$ = diameter of atom = $2\times 67.0\times 10^{-12}m=134.0\times 10^{-12}m$

Now put all the given values in the above formula, we get:

$\Delta v=\frac{6.626\times 10^{-34}Js}{4\times 3.14\times (134.0\times 10^{-12}m)\times (9.11\times 10^{-31}kg)}$

$\Delta v=4.32\times 10^{5}m/s$

The minimum uncertainty in an electron's velocity is, $4.32\times 10^{5}m/s$

Now we have to calculate the percentage of the average speed.

Percentage of average speed = $\frac{\text{Uncertainty in speed}}{\text{Average speed}}\times 100$

Uncertainty in speed = $4.32\times 10^{5}m/s$

Average speed = $1.3\times 10^{6}m/s$

Percentage of average speed = $\frac{4.32\times 10^{5}m/s}{1.3\times 10^{6}m/s}\times 100$

Percentage of average speed = 33.2 % ≈ 33 %

Thus, the percentage of the average speed is, 33 %

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3 years ago

State one difference between solar cells and solar heating systems?

seropon [69]

Solar photovoltaic cells, or solar panels, are arrays of silicon cells that can transforms light radiation into electricity. Solar heating system absorbs the heat from the sun and either transform it into electricity through s generator or uses the energy to heat homes and water.

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4 years ago

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Two forces are applied to a tree stump to pull it out of the ground. Force A has a magnitude of 2410 newtons (N) and points 36.0

Anarel [89]

Answer:

The magnitude of the resultant force is 6201 N

The direction of the resultant force is 72°

Explanation:

Please find the attached file for explanation;

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3 years ago