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5 days ago

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The air is less dense at higher elevations, so skydivers reach a high terminal speed. The highest recorded speed for a skydiver

was achieved in a jump from a height of 39,000 m. At this elevation, the density of the air is only 4.3% of the surface density of air at 20∘C. Estimate the terminal speed of a skydiver at this elevation. Suppose the mass of the skydiver is 90 kg and the cross section area of the skydiver is 0.72 m2. You could consider the diver as a cylinder traveling sideways for this problem.

1 answer:

serg [1.1K]5 days ago

5 0

Answer:

The terminal velocity v_t= 202.96 m/s, approximately 203 m/s.

Explanation:

The formula for terminal velocity is given by

$v_t= \sqrt{\frac{2mg}{\rho AC_d} }$

Here, C_d represents the drag coefficient for the cylindrical shape, which is 1.15.

The air's surface density at 20°C is

ρ_surface = 1.2041 kg/m³.

At an altitude of 39,000 m, the air density is calculated as

ρ = 4.3/100 × 39000 = 0.05177 kg/m³.

Substituting these values back into the formula yields

$v_t= \sqrt{\frac{2\times90\times9.81}{0.05177\times0.72\times1.15} }$

The found terminal velocity v_t is 202.96 m/s, or roughly 203 m/s.

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kicyunya [1011]

Answer:

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8 days ago

Can pockets of vacuum persist in an ideal gas? Assume that a room is filled with air at 20∘C and that somehow a small spherical

kicyunya [1011]

Answer:

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Explanation:

Here is the data provided:

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We calculate the root mean square velocity of air particles. This can be expressed as:

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10 days ago

A bathtub contains 65 gallons of water and the total weight of the tub and water is approximately 931.925 pounds. You pull the p

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We need an expression that shows how much water has been drained from the tub. This is represented by v, which indicates how many gallons have flowed out since the plug was taken out. Each gallon removed equates to 8.345 pounds of water, so the weight of the drained water Q in pounds as a function of v can be expressed as:

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3 days ago

Assume you are driving 20 mph on a straight road. Also, assume that at a speed of 20 miles per hour, it takes 100 feet to stop.

Maru [1053]

Answer:900 feet

Explanation:

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9 days ago

Read 2 more answers

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Yuliya22 [1153]

Answer:

2.45 m

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To begin, we need to determine the book's time of flight, utilizing the equation for vertical motion:

$h=\frac{1}{2}gt^2$

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h = 1.19 m representing the height traveled by the book

g = 9.8 m/s^2 being the gravitational acceleration

t symbolizing the time of flight

By solving for t,

$t=\sqrt{\frac{2h}{g}}=\sqrt{\frac{2(1.19)}{9.8}}=0.49 s$

Next, we calculate the horizontal distance the book travels, defined by

$d=v_x t$

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$v_x = 5.0 m/s$ denotes the horizontal velocity

t = 0.49 s being the time of flight

By substituting,

$d=(5.0)(0.49)=2.45 m$

Thus, the book lands at a distance of 2.45 m.

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7 days ago