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
pantera1 [17]
2 years ago
6

A railroad car of mass 2.50∙10^4 kg is moving at a speed of 4.00 m/s. It collides and couples with three other coupled railroad

cars, each of the same mass as the single car and moving in the same direction with an initial speed of 2.00 m/s.
(a)What is the speed of the four cars after the collision?
(b)How much kinetic energy is lost in the collision? Where does this energy go?
Physics
1 answer:
Vinvika [58]2 years ago
8 0

Answer:

a) v = 1.00 m/s

b) ΔKE = 150 kJ

Lost  energy makes heat, noise, vibration in the system

Explanation:

conservation of momentum

let m be the mass of one car

m(4.00) + 3m(0) = 4mv

v = 1.00 m/s

ΔKE = ½m(4.00)² + ½(3m)(0.00)² - ½(4m)(1.00)²

ΔKE = 8m + 0m - 2m = 6m J

ΔKE = 6(2.50e4) = 150 kJ

You might be interested in
A real battery with internal resistance 0.460 Ω and emf 9.00 V is used to charge a 56.0-µF capacitor. A 21.0-Ω resistor is put i
Margaret [11]

Answer: 1.176×10^-3 s

Explanation: The time constant formulae for an RC circuit is given below as

t =RC

Where t = time constant , R = magnitude of resistance = 21 ohms , C = capacitance of capacitor = 56 uf = 56×10^-6 F

t = 56×10^-6 × 21

t = 1176×10^-6

t = 1.176×10^-3 s

4 0
3 years ago
Read 2 more answers
A centrifuge was used to separate into it’s components. What conclusions out the sample can be formed based on the technique use
Tatiana [17]

-- The sample was a fluid.

-- It was a mixture or a suspension ... NOT a solution.

4 0
3 years ago
What is the impulse of a 3 kg object that starts from rest and moves to 20 m/s?
IrinaK [193]

Answer:

The impulse on the object is 60Ns.

Explanation:

Impulse is defined as the product of the force applied on an object and the time at which it acts. It is also the change in the momentum of a body.

F = m a

F = m(\frac{v_{2}  - v_{1} }{t})

⇒     Ft = m(v_{2} - v_{1})

where: F is the dorce on the object, t is the time at which it acts, m is the mass of the object, v_{1} is its initialvelocity and v_{2} is the final velocity of the object.

Therefore,

impulse = Ft = m(v_{2} - v_{1})

From the question, m = 3kg, v_{1} = 0m/s and v_{2} = 20m/s.

So that,

Impulse = 3 (20 - 0)

             = 3(20)

             = 60Ns

The impulse on the object is 60Ns.

8 0
2 years ago
Like-charged bodies, when brought closer together, will: repel more strongly be neutralized repel less strongly attract more str
SVETLANKA909090 [29]

Answer:

That's almost the true

Explanation:

it does not happen all the time

5 0
2 years ago
Read 2 more answers
Words a child uses are called the spoken or ___ vocabulary
Vaselesa [24]

The answer is: Expressive vocabulary

Expressive vocabulary refers to the combination of all the words that a person has acquire throughout his/her life and can be used in various type of situations.

This would include all words in the child vocabulary, starting from the child's   written language, spoken language or even the child's manually signed words.

4 0
3 years ago
Other questions:
  • Match Newton's laws with their descriptions. 1. Every applied force is opposed by an equal force. 2 .A force must be applied to
    11·1 answer
  • The bob (weight) at the end of a pendulum has a mass of 0.3 kilograms. The bob is pulled to position B and allowed to swing. It
    9·2 answers
  • What type of device is a coal-fired power plant?
    9·1 answer
  • 3) If a ball launched at an angle of 10.0 degrees above horizontal from an initial height of 1.50 meters has a final horizontal
    10·1 answer
  • The speed of an object and direction of its travel is?
    10·1 answer
  • Mixing chemicals in a cold pack creates a reaction that:
    15·2 answers
  • The specific heat of iron is 0.45j/gk. The amount of heat needed to raise the temperature of the 12 g of iron by exactly 15k?
    5·1 answer
  • To appreciate the strength of gravity, calculate the number of steel cables that would be required, in the absence of gravity, t
    7·1 answer
  • It appears as though the moon disappears and the sun comes out in the daytime. Based on what you know, explain why this is happe
    11·2 answers
  • A student drops a ball from a slope. He notices the ball rolling down as shown in the image.
    14·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!