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
yKpoI14uk [10]
3 years ago
14

A subway train starts from rest at a station and accelerates at a rate of 1.68 m/s2 for 14.2 s. It runs at constant speed for 68

.0 s and slows down at a rate of 3.70 m/s2 until it stops at the next station. What is the total distance covered in kilometers?
Physics
2 answers:
andrezito [222]3 years ago
8 0

Answer:

1868.5 m

Explanation:

For AB :

u = 0 m/s

a = + 1.68 m/s^2

t = 14.2 s

Let the distance is s1 and the velocity at B is v.

Use first equation of motion

v = u + at

v = 0 + 1.68 x 14.2 = 23.856 m/s

Use third equation of motion

v^{2}=u^{2}+2as_{1}

23.856^{2}=0^{2}+2\times1.68\times s_{1}

s1 = 169.38 m

For BC:

Let the distance is s2.

s2 = v x t

s2 = 23.856 x 68 = 1622.21 m

For CD:

u = 23.856 m/s

a = - 3.7 m/s^2

v = 0

Let the distance is s3.

Use third equation of motion

v^{2}=u^{2}+2as_{3}

0^{2}=23.856^{2}-2\times 3.7 \times s_{3}

s3 = 76.91 m

The total distance traveled is

s = s1 + s2 + s3

s = 169.38 + 1622.21 + 76.91 = 1868.5 m

Thus, the total distance traveled is 1868.5 m.  

liubo4ka [24]3 years ago
7 0

Answer:

total distance = 1868.478 m

Explanation:

given data

accelerate = 1.68 m/s²

time = 14.2 s

constant time = 68 s

speed = 3.70 m/s²

to find out

total distance

solution

we know train start at rest so final velocity will be after 14 .2 s is

velocity final = acceleration × time      ..............1

final velocity = 1.68 × 14.2

final velocity = 23.856 m/s²

and for stop train we need time that is

final velocity = u + at

23.856 = 0 + 3.70(t)

t = 6.44 s

and

distance = ut + 1/2 × at²     ...........2

here u is initial velocity and t is time for 14.2 sec

distance 1 = 0 + 1/2 × 1.68 (14.2)²

distance 1 = 169.37 m

and

distance for 68 sec

distance 2= final velocity × time

distance 2= 23.856 × 68

distance 2 = 1622.208 m

and

distance for 6.44 sec

distance 3 = ut + 1/2 × at²

distance 3 = 23.856(6.44) - 0.5 (3.70) (6.44)²

distance 3 = 76.90 m

so

total distance = distance 1 + distance 2 + distance 3

total distance = 169.37 + 1622.208 + 76.90

total distance = 1868.478 m

You might be interested in
A tennis racket strikes a tennis ball with a force of 100 N. With what force
viva [34]

Answer:

-100N

Explanation:

Newton's third law of motion states that to every force exerted on one body, there is an equal and opposite force. This means that if object A exerts an ACTION force on B, there is a force called REACTION FORCE, which is equal and opposite, exerted on A by B.

The action and reaction forces are equal in size/magnitude but opposite in direction. In this case where a tennis racket strikes a tennis ball with a force (action force) of 100N, the ball will strike the racket with a reaction force of -100N.

F(RB) = -F(BR)

8 0
2 years ago
Everyday activities do NOT produce significant muscle growth because:
Reil [10]

Answer:

When elements bond together or when bonds of compounds are broken and form a new substance

Explanation:

7 0
3 years ago
Read 2 more answers
A high ____will have a short wavelength.​
Sphinxa [80]

Question:

A high ____will have a short wavelength

Answer:

That means that waves with a high frequency have a short wavelength, while waves with a low frequency have a longer wavelength. Light waves have very, very short wavelengths

Explanation:

Hope it help

4 0
2 years ago
Read 2 more answers
Calculate the density of each ball. Use the formula
mel-nik [20]

Answer:

not 40! i need help

6 0
2 years ago
Read 2 more answers
In 2-3 complete sentences, explain why the needle on a compass always points in the direction of magnetic north.
Alex17521 [72]
The needle on a compass always points in the direction of magnetic north because of the magnetic poles of earth. the compass is essentially a magnet itself, so the southern pole of the compass is attracted to the northern pole of earth.
8 0
3 years ago
Read 2 more answers
Other questions:
  • Many scientists accept a theory about the origin of the universe, called the big bang theory. describe at least one piece of sci
    15·1 answer
  • Which of the following conditions will maximize the amount of interest you earn?
    8·1 answer
  • Which wave diagram BEST represents a dim red sunset on the right side to the light from an intense ultraviolet bug light on the
    9·2 answers
  • Describe a solar eclipse. Be sure to include the positions of the sun, moon, and earth.
    8·1 answer
  • What is the correct definition of a fracture?
    13·1 answer
  • A 20.0-m-tall hollow aluminum flagpole is equivalent in strength to a solid cylinder 4.00 cm in diameter. A strong wind bends th
    6·1 answer
  • why is a train more difficult to stop then a rolling ball even if they are traveling at the same speed? URGENT
    11·1 answer
  • The answer please it’s very simple this is 7th grade science
    13·2 answers
  • Carbon and oxygen react to form carbon dioxide what are the products?
    15·2 answers
  • The fictional rocket ship Adventure is measured to be 65 m long by the ship's captain inside the rocket.When the rocket moves pa
    13·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!