1. What are the 2 main categories of nonmetals?

Write down the effect of humidity and temperature on the speed of sound.

finlep [7]

Answer:

The speed of sound is affected by temperature and humidity. Because it is less dense, sound passes through hot air faster than it passes through cold air. ... The attenuation of sound in air is affected by the relative humidity. Dry air absorbs far more acoustical energy than does moist air.

4 0

3 years ago

Radiation from the Sun The intensity of the radiation from the Sun measured on Earth is 1360 W/m2 and frequency is f = 60 MHz. T

Zina [86]

a) Total power output: $3.845\cdot 10^{26} W$

b) The relative percentage change of power output is 1.67%

c) The intensity of the radiation on Mars is $540 W/m^2$

Explanation:

a)

The intensity of electromagnetic radiation is given by

$I=\frac{P}{A}$

where

P is the power output

A is the surface area considered

In this problem, we have

$I=1360 W/m^2$ is the intensity of the solar radiation at the Earth

The area to be considered is area of a sphere of radius

$r=1.5\cdot 10^{11} m$ (distance Earth-Sun)

Therefore

$A=4\pi r^2 = 4 \pi (1.5\cdot 10^{11})^2=2.8\cdot 10^{23}m^2$

And now, using the first equation, we can find the total power output of the Sun:

$P=IA=(1360)(2.8\cdot 10^{23})=3.845\cdot 10^{26} W$

b)

The energy of the solar radiation is directly proportional to its frequency, given the relationship

$E=hf$

where E is the energy, h is the Planck's constant, f is the frequency.

Also, the power output of the Sun is directly proportional to the energy,

$P=\frac{E}{t}$

where t is the time.

This means that the power output is proportional to the frequency:

$P\propto f$

Here the frequency increases by 1 MHz: the original frequency was

$f_0 = 60 MHz$

so the relative percentage change in frequency is

$\frac{\Delta f}{f_0}\cdot 100 = \frac{1}{60}\cdot 100 =1.67\%$

And therefore, the power also increases by 1.67 %.

c)

In this second case, we have to calculate the new power output of the Sun:

$P' = P + \frac{1.67}{100}P =1.167P=1.0167(3.845\cdot 10^{26})=3.910\cdot 10^{26} W$

Now we want to calculate the intensity of the radiation measured on Mars. Mars is 60% farther from the Sun than the Earth, so its distance from the Sun is

$r'=(1+0.60)r=1.60r=1.60(1.5\cdot 10^{11})=2.4\cdot 10^{11}m$

Now we can find the radiation intensity with the equation

$I=\frac{P}{A}$

Where the area is

$A=4\pi r'^2 = 4\pi(2.4\cdot 10^{11})^2=7.24\cdot 10^{23} m^2$

And substituting,

$I=\frac{3.910\cdot 10^{26}}{7.24\cdot 10^{23}}=540 W/m^2$

Learn more about electromagnetic radiation:

brainly.com/question/9184100

brainly.com/question/12450147

#LearnwithBrainly

4 0

2 years ago

Hello everyone Lubricants are used in machines.Why?Hope u will answer it good day.Thank You✌️

aalyn [17]

Answer:

Lubrication is used to reduce friction. It is generally used for moving machine parts. The lubricants are the substances which are used to reduce the friction which acts between two surfaces in contact, between which relative motion can occur.

4 0

2 years ago

Read 2 more answers

A large meteoroid enters the Earth's atmosphere at a speed of 20.0 km/s and is not significantly slowed before entering the ocea

Shalnov [3]

The shock wave from the meteoroid in the lower atmosphere has a Mach angle of 0.948°.

(a) The meteoroid's speed $v_s=20 \mathrm{~km} / \mathrm{s}$

$=20 \times 10^3 \mathrm{~m} / \mathrm{s}$

Air sound wave speed $&v=331 \mathrm{~m} / \mathrm{s} \\$

Speed of the shock wave in Mach $&\qquad \theta=\sin ^{-1}\left(\frac{v}{v_s}\right)$

$\begin{aligned}&=\sin ^{-1}\left(\frac{331 \mathrm{~m} / \mathrm{s}}{20 \times 10^3 \mathrm{~m} / \mathrm{s}}\right) \\&=0.948^{\circ}\end{aligned}$

Hence, 0.948° is the Mach angle of the shock wave from the meteoroid in the lower atmosphere.

<h3>What is the speed of the meteoroid?</h3>

A meteoroid's speed can be loosely broken down into three categories: slow, medium, and fast.

Slow meteors move around the sun at a leisurely pace of about 32 kilometers per second (20 miles per second).
Medium-speed meteors travel around the sun at approximately 50 kilometers per second (30 miles per second),
while fast meteors zoom past at over 120 kilometers per second (75 miles per second)!

To learn more about meteoroid, visit:

brainly.com/question/1939309

#SPJ4

5 0

1 year ago

Light cannot escape the intense gravitational pull of a _____.

natima [27]

Black hole
hope it helped

3 0

3 years ago

Read 2 more answers