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3 years ago

6

Stacy travels 5 times as fast as Eric. Traveling in opposite directions, they are 336 miles apart after 4 hours. Find their rate

s of travel.

1 answer:

Vilka [71]3 years ago

6 0

Answer:

Eric travelled at 21miles per hour

while stacy travelled at 105miles per hour.

Explanation:

speed = distance/time

then distance = speedxtime.

speed = x

time = 4hrs

Eric's distance after 4hrs = 4x

since stacy is 5 times faster than eric =

stacy's distance = (5x)4 = 20x

Stacy's distance - Eric's distance = 336m

20x - 4x = 336Miles

16x = 336miles

x = 336/16

x = 21miles per hour

so Eric was travelling at 21miles per hour

While Stacy was travelling at 105 miles per hour.

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2 years ago

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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∅ = 89.44°

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In situations like this air resistance are usually been neglected thereby making g= 9.81 m/ $s^{2}$

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

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substituting equation 3 into equation 2

Vertical Distance = d = $V_{1y}$ $\frac{d}{cos o}$ - $\frac{1}{2}$ g $\frac{2}{cos0} ^{2}$

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

Vertical Distance = h = dtan∅ - $\frac{1}{2}$ g $\frac{2}{cos0} ^{2}$

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Vertical Distance = h = d tan∅ - 2 g ( $tan^{2} o$ + 1)

substituting the given parameters

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

800 = 2000 tan ∅ - 19.6( $tan^{2} o$ + 1) Equation 4

Replacing tan ∅ = Q .....................Equation 5

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2 years ago

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<h3>What is Columb's law?</h3>

The force of attraction between two charges, according to Coulomb's law, is directly proportional to the product of the charges and inversely proportional to the square of the distance between them.

Similar charges repel each other, whereas charges that are opposed attract each other.

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From Columb's law;

$\rm F = K \frac{q_1q_2}{d^2} \\\\ 9 \times 10^{-9} = 9 \times 10^9 \frac{q^2}{(7 \times 10^{-4})^2} \\\\ q^2 = 4.9 \times 10^{-25} \\\\ q = 7 \times 10^{-13} \ C$

Hence the charge on each of the equally charged drops of hairspray willl be 7 × 10 ⁻¹³ C

To learn more about Columb's law refer to the link;

brainly.com/question/1616890

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