3 years ago

In which of the following eons did a significant amount of oxygen gas exist in Earth's atmosphere?

Physics

1 answer:

Llana [10]3 years ago

6 0

C that is the answer

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A spherical ball is dropped through a liquid, explain why it reaches terminal velocity.

Alekssandra [29.7K]

Probably because of the drag coefficient and the density of the liquid.

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2 years ago

Which description does the phrase "mechanical advantage" most closely relate to?

yKpoI14uk [10]

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2 years ago

The sine ratio is the ratio formed by the hypotenuse over the side opposite the acute angle. True False

Paha777 [63]

Answer:False

Explanation:

The given statement is false

because the sine ratio is the ratio formed by the side opposite the acute angle to the hypotenuse

$\sin (acute\ angle)=\frac{Perpendicular}{hypotenuse}$

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2 years ago

An object is 45 m above the ground when it is dropped. How fast is the object going just before it hits the ground?

leonid [27]

This is a kinematics question.
$v^{2} = v_{0} ^{2} + 2g(y - y_{0}) \\ 
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3 years ago

Calculate the ratio of the drag force on a jet flying at 1190 km/h at an altitude of 7.5 km to the drag force on a prop-driven t

Bond [772]

Answer:

$\frac{D_{jet}}{D_{prop}}=2.865$

Explanation:

Given data

Speed of jet Vjet=1190 km/h

Speed of prop driven Vprop=595 km/h

Height of jet 7.5 km

Height of prop driven transport 3.8 km

Density of Air at height 10 km p7.8=0.53 kg/m³

Density of air at height 3.8 km p3.8=0.74 kg/m³

The drag force is given by:

$D=\frac{1}{2}CpAv^2\\$

The ratio between the drag force on the jet to the drag force on prop-driven transport is then given by:

$\frac{D_{jet}}{D_{prop}}=\frac{(1/2)Cp_{7.5}Av_{jet}^2}{1/2)Cp_{3.8}Av_{prop}^2} \\\frac{D_{jet}}{D_{prop}}=\frac{p_{7.5}v_{jet}^2}{p_{3.8}v_{prop}}\\\frac{D_{jet}}{D_{prop}}=\frac{(0.53)(1190)^2}{(0.74)(595)^2}\\ \frac{D_{jet}}{D_{prop}}=2.865$

4 0

2 years ago