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3 years ago

Someone help pleaseee! serious answers only. how many miles are in 15,000 feet? 1 mile= 5,280 feet

Physics

2 answers:

Semmy [17]3 years ago

4 0

Have to cross multiply again

1 mi = 5,280 feet
X mi = 15,000 feet

15,000 * 1 / 5,280 = 2.84 miles

The answer is A

DedPeter [7]3 years ago

3 0

The answer is A 2.84 miles. i hope this helps.

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2 years ago

A horizontal spring is attached to the wall on one end and to a mass on the other end. The mass can slide freely on a frictionle

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Answer:

a) x=0 %T=0, b) x= A %T=100%, c) x=-A %T=50%

Explanation:

This is a simple harmonic movement exercise, which is explained by the expression

x = A cos (wt + Ф)

where angular velocity is related to frequency and period

w = 2π f = 2π / T

we can write the equation of the oscillation

x = A cos θ

When seeing the two equations they are equivalent, so what happens with the angle will also happen with time

We are asked for the percentage of the period at three points: at the maximum elongation and at the point of x = 0, in general the distance is measured from the point of the spring without stretching

The period is defined as the time that the system takes to give a complete oscillation, that is, from x = 0 to x = A and return

a) for the unstretched spring point x = 0

In general, both distance and time are measured from this point, so the percentage of time is zero.

% T = 0

b) for x = A

let's find the angle

cos tea = x / A = 1

therefore the angles tea = 2π rad

when the movement reaches the point of 2π radians it begins to repeat so the period is complete

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c) the point of maximum compression x = -A

let's look for the angles

cos tea = x / A = -1

therefore the angles tea = π rad

at this point the movement is halfway so it should take half the time

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2 years ago

3. Una cuerda de guitarra tiene 60 cm de longitud y una masa de 0.05 kg de masa. Si se tensiona mediante una fuerza de 20 N. La

jok3333 [9.3K]

Answer:

f1 = 12.90 Hz

Explanation:

To calculate the first harmonic frequency you use the following formula for n = 1:

$f_n=\frac{n}{2L}\sqrt{\frac{T}{M/L}}$

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It is necessary that the unist are in meters, then you have:

L: length of the string = 60cm = 0.6m

M: mass of the string = 0.05kg

T: tension on the string = 20 N

you replace the values of L, M and T in the expression (1) for getting f1:

$f_1=\frac{1}{2(0.6m)}\sqrt{\frac{20N}{0.05kg/0.6m}}=12.90\ Hz$

Hence, the first harmonic has a frequency of 12.90 Hz

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3 years ago

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Answer:

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As the momentum is conserved

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The speed of the bullet is 217.43298 m/s

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3 years ago

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11111nata11111 [884]

Answer:

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So to calculate the time it took for them to be this far apart

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2 years ago