All categories

3 years ago

Find the color of light whose photon has 4.75x10^-19 J of energy

Physics

1 answer:

shepuryov [24]3 years ago

7 0

Answer:

Explanation:

Energy, E = 4.75 x 10^-19 J

Energy, E = hc/λ

where, λ is the wavelength, h be the Plank's constant and c be the velocity of light.

h = 6.63 x 10^-34 Js

c = 3 x 10^8 m/s

λ = (6.63 x 10^-34 x 3 x 10^8) / (4.75 x 10^-19)

λ = 418.73 nm

So, the colour of light should be violet.

You might be interested in

A radar for tracking aircraft broadcasts a 12 GHz microwave beam from a 2.0-m-diameter circular radar antenna. From a wave persp

NISA [10]

A) 750 m

First of all, let's find the wavelength of the microwave. We have

$f=12GHz=12\cdot 10^9 Hz$ is the frequency

$c=3.0\cdot 10^8 m/s$ is the speed of light

So the wavelength of the beam is

$\lambda=\frac{c}{f}=\frac{3\cdot 10^8 m/s}{12\cdot 10^9 Hz}=0.025 m$

Now we can use the formula of the single-slit diffraction to find the radius of aperture of the beam:

$y=\frac{m\lambda D}{a}$

where

m = 1 since we are interested only in the central fringe

D = 30 km = 30,000 m

a = 2.0 m is the aperture of the antenna (which corresponds to the width of the slit)

Substituting, we find

$y=\frac{(1)(0.025 m)(30000 m)}{2.0 m}=375 m$

and so, the diameter is

$d=2y = 750 m$

B) 0.23 W/m^2

First we calculate the area of the surface of the microwave at a distance of 30 km. Since the diameter of the circle is 750 m, the radius is

$r=\frac{750 m}{2}=375 m$

So the area is

$A=\pi r^2 = \pi (375 m)^2=4.42\cdot 10^5 m^2$

And since the power is

$P=100 kW = 1\cdot 10^5 W$

The average intensity is

$I=\frac{P}{A}=\frac{1\cdot 10^5 W}{4.42\cdot 10^5 m^2}=0.23 W/m^2$

4 0

3 years ago

I need help, ASAP, I know what thermal energy is, but how does a skater use it when on the track?

Flauer [41]

Answer: Looked it up but

Explanation:

When the skater lands on the track, the vertical component of his kinetic energy is converted to thermal energy. You can do experiments where there is no loss to thermal energy (only PE and KE conversions) by turning friction off and by making sure the skater doesn't leave the track.

4 0

3 years ago

Why does it take the water in a swimming pool some time to heat up during a hot day?

BartSMP [9]

Because the top layer of a pool will be warmer than the bottom layer, that why filtration is important to cycle the water evenly.

5 0

3 years ago

Physical data is often used in the court system. In fact, police officers use radar to determine your speed when you are driving

Mashcka [7]

The driver is telling the truth, the radar gun must have been set incorrectly to record relative velocity.

The given parameters:

Speed of the driver observed by the stationary police officer, Vo = 44.7 m/s
Speed of the driver, V = 26.8 m/s.
Speed limit = 60 mph

The speed limit of the driver in meter per second is calculated as follows;

$= 60 \ \times \frac{miles}{hour} \times \frac{1609.34 \ m}{1 \ mile} \times \frac{1 \ hr}{3600 \ s}\\\\= 26.82 \ m/s$

From the speed limit, it is obvious that the driver's speed is within the limit. Thus, we can conclude that the driver is telling the truth, the radar gun must have been set incorrectly to record relative velocity.

Learn more about relative velocity here: brainly.com/question/17228388

6 0

2 years ago

A projectile is shot from the edge of a cliff 80 m above ground level with an initial speed of 60 m/sec at an angle of 30° with

Dvinal [7]

Answer:

8 seconds

Explanation:

Answer:

Explanation:

Going up

Time taken to reach maximum height= usin∅/g

=3 secs

Maximum height= H+[(usin∅)²/2g]

=80+[(60sin30)²/20]

=125 meters

Coming Down

Maximum height= ½gt²

125= ½(10)(t²)

t=5 secs

6 0

3 years ago