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]
2 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]2 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
Does the force of kinetic friction depend on the weight of the block? explain.
drek231 [11]
Yes for an object moving on a horizontal plane, R = mg (where mg = weight). therefore, for an object moving on a horizontal plane: F = μmg



7 0
2 years ago
A 7.5-cmcm-diameter horizontal pipe gradually narrows to 4.5 cmcm . When water flows through this pipe at a certain rate, the ga
tino4ka555 [31]

Answer

given,

diameter,d₁ = 7.5 cm

               d₂ = 4.5 cm

P₁ = 32 kPa

P₂ = 25 kPa

Assuming, we have calculation of flow in the pipe

using continuity equation

 A₁ v₁ = A₂ v₂

 π r₁² v₁ = π r₂² v₂

 v_1= \dfrac{r_2^2}{r_1^2} v_2

 v_1= \dfrac{2.25^2}{3.75^2} v_2

 v_1= 0.36 v_2

Applying Bernoulli's equation

 \Delta P = \dfrac{1}{2}\rho (v_2^2-v_1^2)

 P_1-P_2 = \dfrac{1}{2}\rho (v_2^2-(0.36 v_2)^2)

 32-25 = \dfrac{1}{2}1000\times v_2^2 (1 - 0.1269)

 v_2=\sqrt{\dfrac{2\times 7\times 10^3}{1000\times (0.8704)}}

 v_2=\sqrt{16.084}

       v₂ = 4.01 m/s

fluid flow rate

Q = A₂ V₂

Q = π (0.0225)²  x 4.01

Q = 6.38 x 10⁻³ m³/s

flow in the pipe is equal to 6.38 x 10⁻³ m³/s

4 0
3 years ago
How is the magnetic force on a particle moving in a magnetic field different from gravitational and electric forces.
harina [27]

Answer:

The magnetic force on a free moving charge depends on the velocity of the charge and the magnetic field, direction of the force is given by the right hand rule. While gravitational depends on the mass and distance of the moving particle and electric forces depends on the magnitude of the charge and distance of separation.

Explanation:

The magnetic force on a free moving charge depends on the velocity of the charge and the magnetic field and direction of the force is given by the right hand rule. While gravitational depends on the mass and distance of the moving particle and electric forces depends on the magnitude of the charge and distance of separation.

The magnetic force is given by the charge times the vector product of velocity and magnetic field. While gravitational force is given by the square of the particle mass divided by the square its distance of separation. Also electric forces is given by the square of the charge magnitude divided by the square its distance separation.

4 0
2 years ago
A stone is launched straight up by a slingshot. Its initial speed is 19.6 m/s, and the stone is 1.50 m above the ground when lau
arlik [135]

Answer: a) 19.21m b) 3.92secs

Explanation:

a) Maximum height reached by the object is the height reached by an object before falling freely under gravity.

Maximum height = U²/2g

U is the initial velocity = 19.6m/s

g is acceleration due to gravity = 10m/s²

Maximum Height = 19.6²/2(10)

H = 19.21m

b) The time elapsed before the stone hits the ground is the time of flight T= 2U/g

T= 2(19.6)/10

T = 39.2/10

Time elapsed is 3.92secs

5 0
3 years ago
Five wheels are connected as shown in the figure. Find the velocity of the block “Q”, if it is known that: RA= 5 [m], RB= 10 [m]
Tanzania [10]

Answer:

-5 m/s

Explanation:

The linear velocity of B is equal and opposite the linear velocity of E.

vB = -vE

vB = -ωE rE

10 m/s = -ωE (12 m)

ωE = -0.833 rad/s

The angular velocity of E is the same as the angular velocity of D.

ωE = ωD

ωD = -0.833 rad/s

The linear velocity of Q is the same as the linear velocity of D.

vQ = vD

vQ = ωD rD

vQ = (-0.833 rad/s) (6 m)

vQ = -5 m/s

6 0
2 years ago
Other questions:
  • Which description best matches the image below of a hand that is using the right-hand palm rule?
    14·1 answer
  • Why is gravity considered a force?
    15·2 answers
  • There is a skier at the top of a ski slope. The skier has potential energy. What gives the skier his potential energy? A. his sp
    7·2 answers
  • The sun delivers an average power of 1.499 w/m2 to the top of neptune's atmosphere. find the magnitudes of vector e max and vect
    14·1 answer
  • When merging onto an expressway from an acceleration lane, you should
    10·1 answer
  • A student rapidly rubs the palms of both hands
    8·1 answer
  • Mr. Stephenson drives his car from Dallas to Town X, a distance of 437 km. The trip takes 7.27 hours. What is the average speed
    9·2 answers
  • A) A 12 kg object has a velocity of 37.5 m/s. What is its momentum?
    5·1 answer
  • HELP PLSSS I HAVE AN EXAM MONDAY AND I THINK THIS IS GONNA BE ON ITTTT
    5·1 answer
  • A scientist uses a camera to study the stars.
    7·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!