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3 years ago

A box falls out of a stationary helicopter hovering 135 m above the ground. How long will it take to hit the ground?

1 answer:

4 0

We have the equation of motion $s = ut + \frac{1}{2} at^2$ , where s is the displacement, a is the acceleration, u is the initial velocity and t is the time taken.

Here displacement = 135 m, Initial velocity = 0 m/s, acceleration = 9.81 $m/s^2$

Substituting

$135 = 0*t+\frac{1}{2} *9.8*t^2\\ \\ 4.9t^2 =135\\ \\ t =5.25 seconds$

A box falls out of a stationary helicopter hovering 135 m above the ground will take 5.25 seconds to reach the ground.

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A particular balloon can be stretched to a maximum surface area of 1257 cm2. The balloon is filled with 3.1 L of helium gas at a

chubhunter [2.5K]

Answer:

The ballon will brust at

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Explanation:

Hello!

To solve this problem we are going to use the ideal gass law

PV = nRT

Where n (number of moles) and R are constants (in the present case)

Therefore, we can relate to thermodynamic states with their respective pressure, volume and temperature.

$\frac{P_1V_1}{T_1}=\frac{P_2V_2}{T_2}$ --- (*)

Our initial state is:

P1 = 754 torr

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T1 = 294 K

If we consider the final state at which the ballon will explode, then:

P2 = Pmax

V2 = Vmax

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We also know that the maximum surface area is: 1257 cm^2

If we consider a spherical ballon, we can obtain the maximum radius:

$R_{max} = \sqrt{\frac{A_{max}}{4 \pi}}$

Rmax = 10.001 cm

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Now, from (*)

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2 years ago

In designing circular rides for amusement parks, mechanical engineers must consider how small variations in certain parameters c

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Answer:

Part a)

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Part b)

$dF = \frac{2mvdv}{r}$

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Explanation:

Part a)

As we know that force on the passenger while moving in circle is given as

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now variation in force is given as

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$F = \frac{mv^2}{r}$

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$dF = \frac{2mvdv}{r}$

Part c)

As we know that time period of the circular motion is given as

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so here if radius is constant then variation in time period is given as

$dT = - \frac{2\pi r}{v^2} dv$

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2 years ago

On a caterpillars map all distances are marked in kilometers . The caterpillars map shows the distance between two milkweed plan

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Answer:

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