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4 years ago

Nearly all liquids and solids are nearly opaque to radiation at nearly all wavelengths. why is that

1 answer:

3 0

As radiation enters a solid or liquid, the light waves are absorbed and reflected by the atoms. the resulting reflection from an atom can be in any direction and is random. you can understand opacity in terms of the scattering of radiation. The more opaque, the more scattering.

(The truth is far more complicated than this, check out Richard Feynmans lectures on "Quantum Electro Dynamics" to learn the reality of it. )

You might be interested in

A banana is fired from a cannon on the ground just as a monkey starts to fall from a tree. The monkey catches the banana in mida

Lady bird [3.3K]

Here banana is fired from the canon towards the monkey with certain velocity

while at the same instant when banana is fired money starts to fall from the tree

So here when monkey is in the mid air he catches the banana

It is possible because in the same interval of time when the monkey cover some distance from the tree towards ground then in the same time banana cover the distance from ground towards monkey

So they meet at some point in the mid air

So here since both are moving free in air so they both must have same vertical acceleration

this is acceleration due to gravity

so here correct answer will be

C. The banana and monkey had the same acceleration.

7 0

3 years ago

A car is initially traveling south at a speed of 10.9m/s. The brakes are applied and the car comes to a stop over a distance of

AleksAgata [21]

Answer: $-1.51 m/s^{2}$

Explanation:

Since the car is moving in a single direction, we can use the following kinematic equation to find its acceleration $a$ :

$V^{2}=V_{o}^{2}+2ad$

Where:

$V=0 m/s$ is the car's final velocity (we are told it comes to a stop)

$V_{o}=10.9 m/s$ is the car's initial velocity

$a$ is the car's acceleration

$d=39.2 m$ is the distance travelled by the car

Isolating $a$ :

$a=\frac{V^{2}-V_{o}^{2}}{2d}$

Solving the equation with the given data:

$a=\frac{(0 m/s)^{2}-(10.9 m/s)^{2}}{2(39.2 m)}$

Finally, the acceleration is:

$a=-1.51 m/s^{2}$ Note the negative sign indicates the car was decreasing its velocity before coming to a stop.

8 0

3 years ago

The flywheel of a steam engine begins to rotate from rest with a constant angular acceleration of 1.33 rad/s2. It accelerates fo

Svetradugi [14.3K]

Answer:

We first to know that if the wheel rotates from rest means that at t=0 the velocity and the angle rotated is 0.

Then, we know:

$\alpha = 1.33 = \frac{dw}{dt}$

Integrating 2 times, we have:

$w = 1.33t\\angle =0.665t^{2}$

For the first 27.9 s, we have:

w = 37.107 rad/s

angle = 517.6426 rad

For the next seconds, according to the text, the angular velocity is constant so

w = 37.107 rad/s and hence, integrating:

$angle =37.107t$

Then, the time remaining is:

53.5 - 27.9 = 25.6

So for the next 25.6 seconds we have:

$angle = 37.107*25.6=949.9392 rad$

Finally, we add the 2 angles and we have as a result:

$angle = 517.6426+949.9392=1467.5818$

3 0

3 years ago

A quarterback threw a football at 24 m/s at a 45° angle. If it took the ball 3 seconds to reach the top of its path.

irina1246 [14]

Answer:

6 seconds

Explanation:

If it took the ball 3 seconds to reach the maximum height, then it also took 3 seconds to return to its original height. So it was in the air for a total of 6 seconds.

7 0

4 years ago

What is the effect of the absorption of infrared energy on matter?

barxatty [35]

Answer:

What is the effect of the absorption of infrared energy on matter? It excites bonding electrons. It increases molecular rotation. It breaks chemical bonds.

Explanation:

4 0

3 years ago