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
quester [9]
3 years ago
13

There are two types of waves, mechanical and electromagnetic. Microwaves, infrared, and radio was are examples of electromagneti

c waves. Which statement is true about the speed of an electromagnetic wave?
A) It is not affected by changes in media.
B) It is slower in a vacuum than in a medium.
C) In a vacuum, its speed equals half the speed of light.
D) It slows down when it goes from a vacuum to a medium.
Physics
1 answer:
aivan3 [116]3 years ago
5 0

Answer:

The answer is D.

Explanation:

One explanation I can give you is that generally waves travel faster through denser medium because the particles are tightly packed together and so they can transfer energy faster. But to verify the answer, I used Process of Elimination because the other 3 answers are not true. Choice A is entirely true, wave speed depends on the medium it is travelling through, so there is no way choice A is correct. Choice B is wrong because for example if we take light(an EM wave), it travels at a constant speed of 3.0x10^8 m/s in a vacuum and in open space. So, that proves that air or vacuum do not affect the speed of the wave in another medium. Choice C is related to Choice B, we just proved the speed of light is constant everywhere whereas choice C says that in a vacuum the speed is halved. Good luck in your Physics class and I hope for your best!

You might be interested in
In 2.8 s, a car increases its velocity from 20. M/s to 25 m/s. What is the acceleration of the car
Akimi4 [234]
Acceleration= change in velocity/time; 5/2.8 , so a=1.785714286
6 0
3 years ago
Is silver magnetic or not ?
evablogger [386]

Answer:

Yes, but its magnetic power is very weak so its not that noticeable to the average person whos not paying attention.

4 0
3 years ago
Which would cause the largest increase in a mountain climber’s gravitational potential energy?
Gemiola [76]

Most likely climbing up the mountain

4 0
3 years ago
The answer is 4 but idk how to get it so can somebody please explain how to get it
klemol [59]
How much gravitational potential energy does the block have
when it gets to the top of the ramp ?

      (weight) x (height) = (15 N) x (0.2 m)  =  3 Joules .

If there were no friction, you would only need to do 3 Joules of work
to lift the block from the bottom to the top.

But the question says you actually have to do 4 Joules of work
to get the job done.

Friction stole one of your Joules along the way.

Choice-4 is not the correct one.
Choice-1 is the correct one.

===========================

Notice that the mass of the block is NOT  15 kg , and you
don't have to worry about gravity to answer this question.

The formula for potential energy is  (m)·(g)·(h) .
But (m·g) is just the WEIGHT, and the formula
is actually (weight)·(height).
The question GIVES us the weight of the block . . . 15 N .
So the potential energy at the top is just (15N)·(0.2m) = 3 Joules.
3 0
3 years ago
What does the first law of thermodynamics state about energy?
ruslelena [56]

The first law states that the internal energy change of that system is given by Q − W . Since added heat increases the internal energy of a system, Q is positive when added to the system and negative when removed from the system.

8 0
2 years ago
Other questions:
  • A particular HeNe laser beam at 633 nm has a spot size of 0.8 mm. Assuming a
    5·1 answer
  • Brittany stands at rest on a skateboard. The combined mass of Brittany and the skateboard is 62 kg. Dave tosses a 3.7-kg pumpkin
    11·1 answer
  • A tradesman sharpens a knife by pushing it with a constant force against the rim of a grindstone. The 30-cm-diameter stone is sp
    13·1 answer
  • Copper wire of diameter 0.289 cm is used to connect a set of appliances at 120 V, which draw 1850 W of power total. The resistiv
    5·1 answer
  • Give an example of a system whose mass is not constant.
    5·1 answer
  • * THE ANSWER IS D * Find the location of fluorine (F) on the periodic table. What type of ion will fluorine form?
    8·2 answers
  • Which of these hazmat products are allowed in your FC?
    5·1 answer
  • Why are marble and granite used so often as a building materials?
    10·1 answer
  • Question 12 of 25
    5·2 answers
  • explain the fleming left-hand rule with the diagram and what will the direction of the induced current in the figure if the magn
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!