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3 years ago

Why can't we breath under water?

Physics

2 answers:

Lera25 [3.4K]3 years ago

8 0

Our lungs are not designed breathe oxygen from water to be able to breathe under water.

Kipish [7]3 years ago

5 0

We can certainly draw water into our lungs, even though
our brain screams "Don't do that !".

But our lungs can only separate oxygen out of air, not out of
water. So if there's only water in our lungs, we pass out after
a short time because we're not getting any oxygen.

You might be interested in

Block A, with a mass of 4.0 kg, is moving with a speed of 2.0 m/s while block B , with a mass of 8.0 kg, is moving in the opposi

Anon25 [30]

Consider velocity to the right as positive.

First mass:
m₁ = 4.0 kg
v₁ = 2.0 m/s to the right

Second mass:
m₂ = 8.0 kg
v₂ = -3.0 m/s to the left

Total momentum of the system is
P = m₁v₁ + m₂v₂
= 4*2 + 8*(-3)
= -16 (kg-m)/s

Let v (m/s) be the velocity of the center of mass of the 2-block system.

Because momentum of the system is preserved, therefore
(m₁+m₂)v= -16
(4+8 kg)*(v m/s) = -16 (kg-m)/s
v = -1.333 m/s

Answer:
The center of mass is moving at 1.33 m/s to the left.

5 0

3 years ago

1.)A tank travels at a rate of 10.0 km/hr for 12.00 minutes, then at 15.0 km/hr for 8.00

rosijanka [135]

12.00 min = 0.2 hr

8.00 min = 0.15 hr

Total distance:

(10.0 km/hr) (0.2 hr) + (15.0 km/hr) (0.15 hr) + (20.0 km/hr) (0.2 hr)

= 8.25 km

Average speed:

(10.0 km/hr + 15.0 km/hr + 20.0 km/hr) / 3

= 15 km/hr

Change in position:

(10.0 km/hr) (0.2 hr) + (15.0 km/hr) (0.15 hr) - (20.0 km/hr) (0.2 hr)

= 0.25 km

Average velocity:

(10.0 km/hr + 15.0 km/hr - 20.0 km/hr) / 3

≈ 1.67 m/s

8 0

3 years ago

A biker first accelerates from 0.0 m/s to 6.0 m/s in 6 s, then continues at this speed for 5 s. What is the total distance trave

Svetradugi [14.3K]

Answer:

48m

Explanation:

Given the following data;

Initial velocity = 0m/s

Final velocity = 6m/s

Time, t = 6 secs

Time, T2 = 5 secs

Mathematically, acceleration is given by the equation;

$Acceleration (a) = \frac{final \; velocity - initial \; velocity}{time}$

Substituting into the equation;

$a = \frac{6 - 0}{6}$

$a = \frac{6}{6}$

Acceleration, a = 1m/s²

To find the distance covered in the first phase;

Solving for distance, we would use the second equation of motion;

$S = ut + \frac {1}{2}at^{2}$

Substituting the values into the equation;

$S = 0(6) + \frac {1}{2}*1*(6)^{2}$

$S = 0 + \frac {1}{2}*1*36$

$S = 0.5 *36$

Distance, S1 = 18m

For the second phase, time T2 = 5 secs;

Mathematically, speed is given by the equation;

$Speed = \frac{distance}{time}$

Making distance the subject of formula, we have;

$Distance, S = speed * time$

Substituting into the above equation;

$Distance, S = 6 * 5$

Distance, S2 = 30m

Total distance = S1 + S2 = 18m + 30m = 48m

Total distance = 48m

Therefore, the total distance traveled by the biker is 48m.

4 0

3 years ago

What is pitch related to in terms of sound? Does it affect the speed? If so, how?

Juli2301 [7.4K]

Pitch is the impression the listener gets of the frequency of the sound.

The speed of the sound is not related to its pitch/frequency.

If the speed and frequency were related, that would be a real problem. Bands, orchestras, and choirs could not exist ! All the instruments in the orchestra could play a note together, at the same time. But then the higher instruments ... the flute, trumpet, violins, high guitar strings and high piano keys ... would travel to you fast, and the lower instruments ... the trombone, tuba, double bass, bass drum, low guitar strings and the low piano keys ... would travel to you slow. They all played the note at the same time, but by the time you heard it, it would be all smeared out ... every instrument arriving at your ear at a different time !

5 0

4 years ago

Sarah, who lives in Australia notices that the length of the shadow of the flagpole is getting shorter every day when measured a

Allisa [31]

Answer:

Time zone is one important factor in difference in location and this in turn affects the result of the resolution and rotation of shadow produced from the sun or other illumination.

Therefore someone at a place might see a clear large shadow due to shinny sun reflection and another a small or dull Shadow at same time if the intensity of the sun or lighting source is going down.

Explanation:

The closer a body/object is to a lighting source the larger the shadow it produces, and the farther the body the smaller the shadow produced.

3 0

4 years ago