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
nexus9112 [7]
3 years ago
12

A car drives past a pole at 40km/hr. Describe the motion from the point of view of a) the car, and b) the pole. Thanks in advanc

e! 
Physics
1 answer:
ki77a [65]3 years ago
7 0
I was going to beg off until tomorrow, but this one is nothing like those others.
Why, at only 40km/hr, we can ignore any relativistic correction, and just go with Newton.

To put a finer point on it, let's give the car a direction.  Say it's driving North.

a).  From the point of view of the car, its driver, and passengers if any,
the pole moves past them, heading south, at 40 km/hour .

b).  From the point of view of the pole, and any bugs or birds that may be
sitting on it at the moment, the car and its contents whiz past them, heading
north, at 40 km/hour.

c).  A train, steaming North at 80 km/hour on a track that exactly parallels
the road, overtakes and passes the car at just about the same time as
the drama in (a) and (b) above is unfolding.

The rail motorman, fireman, and conductor all agree on what they have
seen. From their point of view, they see the car moving south at 40 km/hr,
and the pole moving south at 80 km/hr.

Now follow me here . . .

The car and the pole are both seen to be moving south.  BUT ... Since the
pole is moving south faster than the car is, it easily overtakes the car, and
passes it . . . going south.

That's what everybody on the train sees.

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

Finally ... since you posed this question as having something to do with your
fixation on Relativity, there's one more question that needs to be considered
before we can put this whole thing away:

You glibly stated in the question that the car is driving along at 40 km/hour ...
AS IF we didn't need to know with respect to what, or in whose reference frame.
Now I ask you ... was that sloppy or what ? ! ? 

Of course, I came along later and did the same thing with the train, but I am
not here to make fun of myself !  Only of others.

The point is . . . the whole purpose of this question, obviously, is to get the student accustomed to the concept that speed has no meaning in and of itself, only relative to something else.  And if the given speed of the car ...40 km/hour ... was measured relative to anything else but the ground on which it drove, as we assumed it was, then all of the answers in (a) and (b) could have been different.

And now I believe that I have adequately milked this one for 50 points worth.


You might be interested in
a kid on a playground swing makes 6 complete to-and-from swings each 30 seconds (a) the frequency of the swinging is? (b) the pe
Mariana [72]

The frequency is how many per second:

       (6 swings)/(30 sec) = (6/30) swing/sec = 0.2 per sec = 0.2 Hz .

The period is how long each one takes, or seconds per swing.
It's exactly the flip of frequency.
So we could just take the frequency, flip it, and find   1 / 0.2 ,
but let's do it the long way:

      (30 sec) / (6 swings) = (30/6) sec/swing =  5 seconds  .  

      
4 0
3 years ago
Read 2 more answers
PLEASE HELP EMERGENCY
sweet [91]

Answer:

mechanical energy to heat energy to chemical energy

8 0
2 years ago
As your rockets went upwards how would you describe how the energies changed?
chubhunter [2.5K]

As a rocket increases height and slows down, it gains more and more potential energy and loses more and more kinetic energy. Potential energy is store energy (usually determined by height), and kinetic energy increases as speed increases.

4 0
2 years ago
A magnetically soft material is placed in a strong magnetic field. What is the most likely outcome?
MakcuM [25]

Answer:

It will become a temporary magnet because the domains will easily realign.

Explanation:

3 0
3 years ago
Two iron weights, one twice the mass of the other, are dropped from the top of a building. Compared with the lighter weight, the
Whitepunk [10]
The twice as heavy weight will hit the ground with more force, or impact.
4 0
3 years ago
Read 2 more answers
Other questions:
  • The molecule that traps the sun's energy is ?.
    13·1 answer
  • The velocity of waves in a ripple tank is 20 centimeters per second, and standing waves are produced with nodes spaced 3.0 centi
    8·1 answer
  • A roller coaster is traveling at 13 m/s when it approaches a hill that is 400 m long. Heading down the hill, it accelerates at 4
    8·2 answers
  • Is it possible for a baseball to have as large a momentum as a much more massive bowling ball
    13·1 answer
  • Which identifies that a chemical reaction has occurred?
    9·1 answer
  • 2 Pont
    10·1 answer
  • The gravitational force between two asteroids is 100N. What would the force be if the distance between the asteroids was cut in
    8·1 answer
  • Which forces are capable of affecting particles or objects from large distance
    15·1 answer
  • From what three regions do most of the small objects in the universe come?
    12·1 answer
  • !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!