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
Aleks04 [339]
3 years ago
11

Can someone answer these?

Physics
1 answer:
natita [175]3 years ago
4 0

Short Answer

3: C

4: D

Problem Three

Remark

Somewhere we ought to be told that this is the Doppler Effect. I have never done a problem using this formula, so I think I'm doing it correctly, but no guarantees. My guess is that the frequency increases as it comes towards you and decreases as it moves away from you. I think that is correct.

Formula

<em><u>Givens</u></em>

  • f' = observed frequency
  • f = actual frequency
  • v = velocity of sound or light waves.
  • vo = velocity of observer (in both cases 0)
  • vs = velocity of source.

f' = (v + vo) * f / (v - vs)

Solution

  • v = 3*10^8 m/s
  • f' = 1.1 f
  • f = f
  • vo = 0  We are standing still while all this is going on.
  • vs = ???

f'/f = 1.1

1.1 = (3*10^8  + 0 ) / (3*10^8 - vs)

3.3*10^8 - 1.1*vs = 3*10^8

3.3*10^8 - 3*10^8= 1.1 vs

0.3 * 10^8 = 1.1 vs

2.73 * 10^7 = vs

The closest answer is 3.00 * 10^7 which is C

Problem Four

Here what is happening is that you are looking for the frequency resulting from a wave moving towards you at 1/2 the speed of sound. You are not moving.

<em><u>Givens</u></em>

  • v = v
  • vs = 1/2 v
  • f ' = ?
  • f = 1000 hz
  • vo =0

f' = v/(v - 1/2v) * 1000

f' = v/ (1/2 v) * 1000

f' = 2 * 1000

f' = 2000 which is D

You might be interested in
9. (02.04 LC)
ycow [4]

Answer:

Molecules speed up

Explanation:

This is caused because of the temperature increasing. The temperature increase is telling us that the thermal energy of the reaction is increasing. When the energy is increased molecules increase their speed, because they have more energy in them

7 0
3 years ago
When distances were carefully measured from the Earth to globular clusters above and below the Milky Way plane (where our view o
uranmaximum [27]

Answer:

A) Spherically symmetric about a point in the constellation Sagittarius and concentrated in that direction

Explanation:

The globular clusters are present mainly in the direction of Sagittarius with the center of the system of globular cluster being measured as a spherical cluster cloud such that the center of the Milky Way can be taken as being in the Sagittarius constellation

4 0
3 years ago
if you have 10,000 red blood cells, how many red blood cells and white blood cells do you have altogether
ivolga24 [154]
I believe its 17,000 blood cells in your body 

6 0
3 years ago
What is the net electrical charge on a magnesium ion that is formed when a neutral magnesium atom loses two electrons?
Arisa [49]
-3.2x10^-19C is formed 
4 0
3 years ago
Read 2 more answers
A ball of mass 0.160 kg is dropped from a height of 2.25 m. When it hits the ground it compresses 0.087 m.
Studentka2010 [4]

A) 6.64 m/s downward

B) 0.026 s

C) -40.9 N

Explanation:

A)

We can solve this problem by using the law of conservation of energy.

In fact, since the total mechanical energy of the ball must be conserved, this means that the initial gravitational potential energy of the ball before the fall is entirely converted into kinetic energy just before it reaches the floor.

So we can write:

PE=KE\\mgh = \frac{1}{2}mv^2

where

m = 0.160 kg is the mass of the ball

g=9.8 m/s^2 is the acceleration due to gravity

h = 2.25 m is the initial height of the ball

v is the final velocity of the ball before hitting the ground

Solving for v, we find:

v=\sqrt{2gh}=\sqrt{2(9.8)(2.25)}=6.64 m/s

And the direction of the velocity is downward.

B)

The motion of the ballduring the collision is a uniformly accelerated motion (= with constant acceleration), so the time of impact can be found by using a suvat equation:

s=(\frac{u+v}{2})t

where:

v is the final velocity

u is the initial velocity

s is the displacement of the ball during the impact

t is the time

Here we have:

u = 6.64 m/s is the velocity of the ball before the impact

v = 0 m/s is the final velocity after the impact (assuming it comes to a stop)

s = 0.087 m is the displacement, as the ball compresses by 0.087 m

Therefore, the time of the impact is:

t=\frac{2s}{u+v}=\frac{2(0.087)}{0+6.64}=0.026 s

C)

The force exerted by the floor on the ball can be found using the equation:

F=\frac{\Delta p}{t}

where

\Delta p is the change in momentum of the ball

t is the time of the impact

The change in momentum can be written as

\Delta p = m(v-u)

So the equation can be rewritten as

F=\frac{m(v-u)}{t}

Here we have:

m = 0.160 kg is the mass of the ball

v = 0 is the final velocity

u = 6.64 m/s is the initial velocity

t = 0.026 s is the time of impact

Substituting, we find the force:

F=\frac{(0.160)(0-6.64)}{0.026}=-40.9 N

And the sign indicates that the direction of the force is opposite to the direction of motion of the ball.

4 0
3 years ago
Other questions:
  • Which of the following is a supersonic speed? Mach 0.005 Mach 0.05 Mach 0.5 Mach 5
    10·2 answers
  • What is steam engine it's action and reaction​
    14·1 answer
  • There are 4.2 cups in a liter. of a bottle holds 2.0 cups what does it hold in liters
    10·2 answers
  • Acceleration of 1.5 ms expressed in km /hr2? ​
    9·1 answer
  • Suppose that you find in a reference book that the volume of all the oceans is 1.4×109km3. To find the mass, you can use the den
    6·1 answer
  • Why does the area around the equator stay the same temperature year-round
    8·1 answer
  • Since monsoons are storms that usually occur during a specific time of year in certain regions, you could not compare them to th
    13·2 answers
  • Plate] term 3 quiz 1 physics grade 9
    8·1 answer
  • In a line graph the dependent variable is plotted on the
    6·1 answer
  • Hello, I wanted an answer from a mathematician. The number 1.04 is closer to the number 1, 2, 1.25 or 1.5.
    14·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!