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the density of dry air at 20 degrees celsius is 1.20 g/L. What is the mass of air, in kilograms, of a room that measures 24.0m b

horsena [70]

<h2>Mass of air in a room that measures 24.0 m by 15.0 m by 4.0 m is 1728 kg.</h2>

Explanation:

Density of air = 1.20 g/L = $\frac{1.20\times 10^{-3}kg}{10^{-3}m^3}=1.2kg/m^3$

Size of room is 24.0m by 15.0 m by 4.0 m

Volume of room = 24 x 15 x 4 = 1440 m³

We know the equation

Mass = Volume x Density

Mass = 1440 x 1.2

Mass = 1728 kg

Mass of air in a room that measures 24.0 m by 15.0 m by 4.0 m is 1728 kg.

8 0

3 years ago

Which has more friction? wax paper, aluminum foil, wood

Nadusha1986 [10]

The answer to this is aluminum foil.

5 0

3 years ago

Read 2 more answers

Explain the Big Bang and how it started

AlexFokin [52]

The big bang is how astronomers explain the way the universe began. It is the idea that the universe began as just a single point, then expanded and stretched to grow as large as it is right now (and it could still be stretching).

7 0

3 years ago

Read 2 more answers

How many times does a human heart beat during a person’s lifetime? How many gallons of blood does it pump? (Estimate that the he

Nostrana [21]

Answer: The heart pumps 124.2 billion cm³ of blood in a lifetime

Explanation:

as an adult the pulse rate average must be around 72 beats per minute.

The heart beats about 103,680 times in a day.

There are 365 days in a year

number of heart beat in a year = 365 days x 103,680 = 37,843,200 beats in a year

For every the heart pumps 50cm³ of blood,

Hence,

Amount of blood pump in a year = 50 x 37,843,200 = 1,892,160,000cm³ of blood pumped in a year.

Using the estimated lifespan average an individual is 69 years

So in a life time,

The human heart pumps = 1,892,160,000 x 69 years = 124,200,000,000

If the heart pumps 50cm³ of blood per beat, the heart pumps a total of 130,559,040,000 cm³ (130.6 billion cm³) of blood in a LIFETIME.

3 0

3 years ago

How does a substance's temperatura chanté when the average kinetic energy of its particles increases? When it decreases?

Aleks [24]

Kinetic energy means movement. This means that the more something moves, the more kinetic energy it will have! And the faster something moves, the more heat it produces! Altogether, this means that the more Kinetic energy something has, the hotter it will be!

The opposite is also true. The less something moves, it will have less Kinetic energy and the colder it will get.

If you're having trouble understanding this, think of it like how the particles in water move compared to how the particles in ice move. The particles in water are free flowing and can move wherever they want. If they get colder, they won't move as much, and eventually they'll stop flowing around, forming a solid and staying colder than the water will get.

7 0

3 years ago

Are these right? Just need you to confirm or tell we what I got wrong. Thanks​

Are these right? Just need you to confirm or tell we what I got wrong. Thanks