1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Alinara [238K]
3 years ago
13

UVC light used in sterilizers, has wavelengths between 100 to 280 nm. If a certain UVC wave has a wavelength of 142.9 nm, what i

s the energy of one of its photons in J
Physics
1 answer:
Harlamova29_29 [7]3 years ago
6 0

Answer:

The energy of one of its photons is 1.391 x 10⁻¹⁸ J

Explanation:

Given;

wavelength of the UVC light, λ = 142.9 nm = 142.9 x 10⁻⁹ m

The energy of one photon of the UVC light is given by;

E = hf

where;

h is Planck's constant = 6.626 x 10⁻³⁴ J/s

f is frequency of the light

f = c / λ

where;

c is speed of light = 3 x 10⁸ m/s

λ  is wavelength

substitute in the value of f into the main equation;

E = hf

E = \frac{hc}{\lambda} \\\\E = \frac{6.626*10^{-34} *3*10^{8}}{142.9*10^{-9}} \\\\E = 1.391*10^{-18} \ J

Therefore, the energy of one of its photons is 1.391 x 10⁻¹⁸ J

You might be interested in
Electromagmetic radiation comes in different forms which pair does not appear next to one an other in the electromagmetic spectr
vivado [14]

Answer:

A) microwaves and ultraviolet

Explanation:

this is the spectrum in order:

radio waves

microwaves

infra red

visible light

ultraviolet

X rays

gamma rays

6 0
2 years ago
What was the greatest discovery by galileo during his inclined-plane experiments?
Sergeeva-Olga [200]
Galileo discovered during his inclined-plane experiments that a ball rolling down an incline and onto a horizontal surface would roll indefinitely.
3 0
3 years ago
Which best describes a similarity between power plants that use water as an energy source and those that use wind as an energy s
disa [49]
The hydropower plant and wind turbines both uses kinetic energy to produce mechanical power and convert the mechanical energy using a generator to an electrical energy. They both have the process to produce energy but they differ in the source the hydropower plant uses water to whit the wind turbines power plant uses wind. Therefore the answer is letter B. 
3 0
3 years ago
Read 2 more answers
Melvin is traveling south on I-95 at 29 m/s (65 mph) when a deer jumps into his path, 50 m ahead. a. If his reaction time is 0.1
aleksandr82 [10.1K]

Answer:

a. 5.22 meters

b. 2.9 seconds

c. No, Melvin does not hit the deer

Explanation:

The parameters with which Melvin is travelling are as follows;

The speed of Melvin's motion, u = 29 m/s

The distance from Melvin at which the deer jumps into the path = 50 m

a. Distance, d = Velocity, u × Time, t

The time it takes Melvin to react = 0.18 seconds

The distance, "d₁" Melvin travels before his foot hits the break = The velocity with which Melvin was traveling, "u" × The time duration it takes Melvin to hit the brakes, "t₁"

∴ d₁ = 29 m/s × 0.18 s = 5.22 m

The distance, Melvin travels before his foot hits the break = d₁ = 5.22 m

b. Melvin's acceleration after his foot hits the brakes, a = -10 m/s²

Therefore, we have;

The time it takes "t₂" it takes for him to come to a complete stop given as follows;

y = u + a × t₂

Where;

v = The final velocity after Melvin comes to a complete stop = 0 m/s

By substituting the known values, we have;

0 = 29 m/s + (-10 m/s²) × t₂ = 29 m/s - 10 m/s² × t₂

∴ 29 m/s = 10 m/s² × t₂

t₂ = (29 m/s)/(10 m/s²) = 2.9 s

The time it takes it takes for him to come to a complete stop = t₂ = 2.9 s

c. The distance, "d₂", Melvin reaches while accelerating (decelerating) at -10 m/s² to come to a complete stop is given as follows;

v² = u² + 2·a·d₂

Therefore, we have;

0² = (29 m/s)² + 2 × (-10 m/s) × d₂ = (29 m/s)² - 2 × 10 m/s × d₂

∴  (29 m/s)² = 2 × 10 m/s × d₂

d₂ = ((29 m/s)²)/(2 × 10 m/s²) = (841 m²/s²)/(20 m/s²) = 42.05 m

The distance, Melvin reaches while accelerating (decelerating) at -10 m/s² to come to a complete stop = d₂ = 42.05 m

Given that d₂ = 42.05 m < 50 m (The distance separating Melvin's initial location and the deer, Melvin does not hit the deer.

3 0
3 years ago
Yes or no
Tju [1.3M]

Answer:

1. No, it is a colloid

2. Yes

Explanation:

8 0
2 years ago
Other questions:
  • Assume you are a perfect blackbody at a temperature of T = 310 K. What is the rate, in watts, at which you radiate energy? (For
    13·1 answer
  • What is the mass of a 4900 n bobsled?
    7·1 answer
  • Josh has a toy car of mass 3 kg tied to a string of length 2 m. He ties the string to a pole and has the toy car drive in a circ
    10·2 answers
  • Commander Shepard, an N7 spectre for Earth, weighs 799 N on the Earth's surface. When she lands on Noveria, a distant planet in
    10·1 answer
  • You are building a uniform to protect workers from all types of nuclear radiation. If you use material that blocks _____ radiati
    5·1 answer
  • A 2.0-kg ball with an initial velocity of (4i + 3j) m/s collides with a wall and rebounds with a velocity of (–4i + 3j) m/s. Wha
    14·1 answer
  • A red car has a head-on collision with an approaching blue car with the same magnitude of momentum. A green car driving with the
    6·2 answers
  • A wire of radius 0.8 cm carries a current of 106 A that is uniformly distributed over its cross-sectional area. Find the magneti
    7·1 answer
  • Can someone help me due at 1:00 PM plus 100 points <br><br>questions B,C,D
    12·2 answers
  • Question 1 of 12
    8·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!