Which of the following is NOT a characteristic of noble gases?

ELEN [110]

Answer:

Hey

Unlike visible light, X-rays can go through you without getting absorbed. But some of it gets absorbed but most of it passes through, this tiny bit that does get absorbed shows you the image of the baby.

7 0

3 years ago

Which situations might cause two observers (A and B) to measure different frequencies for the same vibrating object? Select the

Alex787 [66]

We want to explain why two different observes may measure different frequencies for the same vibrating object.

We will see that the two correct options are:

Observer A is stationary and Observer B is moving.
Observer A and Observer B are moving at different speeds relative to each other.

Let's assume that the vibrating object is a guitar string. Thus, the string makes a noise, and from that noise, we can estimate the frequency at which the string vibrates.

Now there appears a really cool effect, called the Doppler Effect. It says that the apparent change of frequency is due to the motion of the observer or the source of the frequency (or both).

For example, if you move towards the vibrating string, the perceived frequency will be larger, and you will hear a "higher" sound.

While if you move away from the string, the opposite happens, and you will hear a "lower" sound.

Then the only thing that impacts in how we perceive the frequency is our velocity relative to the source.

So, why do observers A and B measure different frequencies?

The two correct answers are:

Observer A is stationary and Observer B is moving.
Observer A and Observer B are moving at different speeds relative to each other.

If you want to learn more, you can read:

brainly.com/question/17107808

6 0

3 years ago

Plzzzzzzzzzz!!!!!!! Hurryyyyy

Scilla [17]

Answer:

student A or B

Explanation:

A common demonstration is to put a ringing alarm clock or bell in the bell jar, and when the vacuum is created, you can no longer hear the sound of the clock/bell.

The bell is connected to a lab pack or batteries and rung to show pupils it can be heard under normal circumstances. The bell jar is then connected to a vacuum pump using a vacuum plate (see Fig 2) and the air is removed from inside creating a near vacuum. The bell is then again rung. This time however, it cannot be heard.

Small low voltage buzzers can be used as a bell replacement for the bell and work in exactly the same way though teachers generally prefer bells as students may be able to see the hammer moving, proving that it is actually ringing even though they cannot hear it.

Some vacuum pumps are better than others at keeping a strong vacuum though if you cannot completely lose the sound, you will at least notice the volume decreasing.

Sound is simply a series of longitudinal waves travelling from the source, through the air to our ears. Without air present, these waves cannot form and therefore sound cannot be conveyed.

In a longitudinal wave the particles oscillate back and forth in the direction of the wave movement unlike transverse waves which like waves on the sea, single particles travel up and down and not in the direction of the wave.

Because you will not be able to create a perfect vacuum, you may still be able to hear the bell ring slightly. Vibrations from the ringing bell can also travel up to the bung in the bell jar which in turn may resonate the jar slightly. This means you may hear the bell ring, however strong the vacuum. To compensate for this, try to insulate the bell as much as possible from the bell jar. Hanging the bell using elastic cord means some of the vibrations will be absorbed by the cord and not be transferred to the bell jar.

3 0

3 years ago

9. Calculate the distance (in km) that Charlie runs if he maintains the average

Karo-lina-s [1.5K]

Correct Question:

Calculate the distance (in km) charlie runs if he maintains an average speed of 8 km/hr for 1 hour

Answer:

The total distance covered by Charlie is 8 km in 1 hour.

Explanation:

The average velocity as given in the question is,

v = 8 km/hr

Total time taken,

$$t=1 hour$

As we know the formula to evaluate the total distance d when the average velocity and time is given;

$v=\frac{d}{t}$

$d=v \times t$

$d=8 \times 1$

$d=8 k m$

Hence, the total distance covered by Charlie in 1 hour will be 8 km.

5 0

3 years ago

An artificial satellite circles Earth in a circular orbit at a location where the acceleration due to gravity is 9.00 m/s2. Dete

Ksju [112]

g = GMe/Re^2, where Re = Radius of earth (6360km), G = 6.67x10^-11 Nm^2/kg^2, and Me = Mass of earth. On the earth's surface, g = 9.81 m/s^2, so the radius of your orbit is:

R = Re * sqrt (9.81 m/s^2 / 9.00 m/s^2) = 6640km

here, the speed of the satellite is:

v = sqrt(R*9.00m/s^2) = 7730 m/s

the time it would take the satellite to complete one full rotation is:

T = 2*pi*R/v = 5397 s * 1h/3600s = 1.50 h

Hope it help i know it's long and may be confusing but if you have any more questions regarding this topic just hmu! :)

6 0

3 years ago