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
Fantom [35]
3 years ago
13

If the maximum acceleration that is tolerable for passengers in a subway train is 1.21 m/s2 and subway stations are located 810

m apart, what is the maximum speed a subway train can attain between stations
Physics
1 answer:
Rasek [7]3 years ago
7 0

Answer:

v = 44.27 m / s

Explanation:

This is an exercise in kinematics since they ask the maximum speed of the train

           v² = v₀² + 2 a x

a train departs with zero initial velocity

           v² = 2 a x

           v = √ 2ax

calculate

           v = √ (2 1.21 810)

            v = 44.27 m / s

in this solution we have assumed that the train uses the entire distance with acceleration

You might be interested in
A projectile of mass 2.0 kg is fired in the air at an angle of 40.0 ° to the horizon at a speed of 50.0 m/s. At the highest poin
tekilochka [14]

Answer:

a) The fragment speeds of 0.3 kg is 33.3 m / s on the y axis

                                         0.7 kg is 109.4 ms on the x axis

b)  Y = 109.3 m

Explanation:

This is a moment and projectile launch exercise.

a) Let's start by finding the initial velocity of the projectile

       sin 40 = voy / v₀

       v_{oy} = v₀ sin 40

       v_{oy} = 50.0 sin40

       v_{oy} = 32.14 m / s

       cos 40 = v₀ₓ / V₀

       v₀ₓ = v₀ cos 40

       v₀ₓ = 50.0 cos 40

       v₀ₓ = 38.3 m / s

Let us define the system as the projectile formed t all fragments, for this system the moment is conserved in each axis

Let's write the amounts

Initial mass of the projectile M = 2.0 kg

Fragment mass 1 m₁ = 1.0 kg and its velocity is vₓ = 0 and v_{y} = -10.0 m / s

Fragment mass 2 m₂ = 0.7 kg moves in the x direction

Fragment mass 3 m₃ = 0.3 kg moves up (y axis)

Moment before the break

X axis

     p₀ₓ = m v₀ₓ

Y Axis y

    p_{oy} = 0

After the break

X axis

   p_{fx} = m₂ v₂

Axis y

     p_{fy} = m₁ v₁ + m₃ v₃

Let's write the conservation of the moment and calculate

Y Axis  

     0 = m₁ v₁ + m₃ v₃

Let's clear the speed of fragment 3

     v₃ = - m₁ v₁ / m₃

     v₃ = - (-10) 1 / 0.3

     v₃ = 33.3 m / s

X axis

     M v₀ₓ = m₂ v₂

     v₂ = v₀ₓ M / m₂

     v₂ = 38.3  2 / 0.7

     v₂ = 109.4 m / s

The fragment speeds of 0.3 kg is 33.3 m / s on the y axis

                                         0.7 kg is 109.4 ms on the x axis

b) The speed of the fragment is 33.3 m / s and has a starting height of where the fragmentation occurred, let's calculate with kinematics

       v_{fy}² = v_{oy}² - 2 gy

       0 =  v_{oy}²-2gy

       y =  v_{oy}² / 2g

       y = 32.14² / 2 9.8

       y = 52.7 m

This is the height where the break occurs, which is the initial height for body movement of 0.3 kg

      v_{f}² =  v_{y}² - 2 g y₂

      0 =  v_{y}² - 2 g y₂

     y₂ =  v_{y}² / 2g

     y₂ = 33.3²/2 9.8

     y₂ = 56.58 m

Total body height is

      Y = y + y₂

      Y = 52.7 + 56.58

     Y = 109.3 m

8 0
2 years ago
Calculate the tangential speed of a yo-yo twirled at the end of a 4 meter long string at 2 revolutions per second.
Oliga [24]

Answer: 50 m/s

Explanation: speed v = 2· pi·n·r = 2· 3.14· 2 s^-1· 4 m

8 0
2 years ago
in 1859 a hunter brought 24 rabbits from England to Australia and release them to establish a population for sport hunting rabbi
slavikrds [6]
I would say the rabbits were breeding.
4 0
3 years ago
Experiment: Limestone
White raven [17]
When these bonds are destroyed, a reaction occurs. ... Vinegar reacting with limestone breaks the bonds of calcium carbonate and acetic acid.
7 0
3 years ago
A rock is thrown off a 50.0 m high cliff. How fast must the rock leave the cliff top to land on level ground below, 90 m from th
blagie [28]

Answer:

The rock must leave the cliff at a velocity of 28.2 m/s

Explanation:

The position vector of the rock at a time t can be calculated using the following equation:

r = (x0 + v0x · t, y0 + 1/2 · g · t²)

Where:

r = position vector at time t.

x0 = initial horizontal position.

v0x = initial horizontal velocity.

t = time.

g = acceleration due to gravity (-9.81 m/s² considering the upward direction as positive).

Please, see the attached figure for a graphical description of the problem. Notice that the origin of the frame of reference is located at the edge of the cliff so that x0 and y0 = 0.

When the rock reaches the ground, the position vector will be (see r1 in the figure):

r1 = (90 m, -50 m)

Then, using the equation of the vector position written above:

90 m = x0 + v0x · t

-50 m = y0 + 1/2 · g · t²

Since x0 and y0 = 0:

90 m = v0x · t

-50 m = 1/2 · g · t²

Let´s use the equation of the y-component of the vector r1 to find the time it takes the rock to reach the ground and with that time we can calculate v0x:

-50 m = 1/2 · g · t²

-50 m = -1/2 · 9.81 m/s² · t²

-50 m / -1/2 · 9.81 m/s² = t²

t = 3.19 s

Now, using the equation of the x-component of r1:

90 m = v0x · t

90 m = v0x · 3.19 s

v0x = 90 m / 3.19 s

v0x = 28.2 m/s

8 0
3 years ago
Other questions:
  • A blackbody curve relates _____. intensity of radiation to energy intensity of radiation to wavelength wavelength to energy surf
    11·2 answers
  • Choose the list below that properly arranges objects in the Solar System (from closest to farthest from the center). Select one:
    13·2 answers
  • The town of seaside needs to build a new power plant the old coal burning plant produces too much pollution and if no longer saf
    5·1 answer
  • Does lightning come from the ground? I have heard that lightning comes from the ground up. But when it strikes something on land
    8·2 answers
  • 22. In an experiment to determine the density of a soil using a density bottle, the following measuren were recorded. Mass of em
    7·1 answer
  • No work is said to be done by standing man carrying 500kg load.why?​
    12·1 answer
  • What is the Hairdryer energy transfers
    13·1 answer
  • 5) The max, height reached by a bike rider is 250m after she reaches top speed and then
    12·1 answer
  • A spring stretches 2 meters when a 12 N force is acting on it. What is the spring constant (k)? 10 N/m 0.17 N/m 2 N/m 6 N/m
    13·1 answer
  • 16) A car's position in relation to time is plotted on the graph. What can be said about the car during segment B?
    6·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!