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
Natali [406]
1 year ago
10

A 500 kg sack of coal falls vertically onto a 2000 kg railroad flatcar which was initially moving horizontally at 3 m/s. no exte

rnal forces, including friction, act on the flatcar. after the sack rests on the flatcar, the speed of the flatcar is:
Physics
1 answer:
Zinaida [17]1 year ago
6 0

Since there are no external forces, including friction, act on the flatcar. after the sack rests on the flatcar, we would assume that momentum is conserved. This means that

total momentum of car before collision = total momentum of car after collision.

Recall,

momentum = mass x velocity

From the information given,

mass of car before collision = 2000

velocity of car before collision = 3

Thus,

total momentum of car before collision = 2000 x 3 = 6000

Also,

mass of sack = 500

mass of car and sack after collision = 500 + 2000 = 2500

velocity after collision = v

momentum after collision = 2500 x v = 2500v

Since momentum is conserved, then

6000 = 2500v

v = 6000/2500

v = 2.4

the speed of the flatcar is 2.4 m/s

You might be interested in
Can an element be a molecule
Serga [27]

an element can make a molecule. so technically yes.

6 0
3 years ago
Read 2 more answers
a 0.0780 kg lemming runs off a 5.36 m high cliff at 4.84 m/s. what is its potential energy (PE) when it is 2.00 m above the grou
zmey [24]

Answer:

1.56 J

Explanation:

The potential energy only depends on the vertical height from the ground level.

We consider the ground level to have zero P.E.

So when it is 2 m above the ground level,

P.E. =  mgh

      = 0.078×10×2

      = 1.56 J

7 0
3 years ago
Un neumático sin cámara, soporta una presión de 1.5 atm cuando la temperatura ambiente es de 300°K. ¿Qué presión llegará a sopor
arlik [135]

Answer:

El neumático soportará una presión de 1.7 atm.

Explanation:

Podemos encontrar la presión final del neumático usando la ecuación del gas ideal:

PV = nRT

En donde:

P: es la presión

V: es el volumen

n: es el número de moles del gas

R: es la constante de gases ideales

T: es la temperatura

Cuando el neumático soporta la presión inicial tenemos:

P₁ = 1.5 atm

T₁ = 300 K

V_{1} = \frac{nRT_{1}}{P_{1}}  (1)  

La presión cuando T = 67 °C es:

P_{2} = \frac{nRT_{2}}{V_{2}}   (2)

Dado que V₁ = V₂  (el volumen del neumático no cambia), al introducir la ecuación (1) en la ecuación (2) podemos encontrar la presión final:

P_{2} = \frac{nRT_{2}}{V_{2}} = \frac{nRT_{2}}{\frac{nRT_{1}}{P_{1}}} = \frac{P_{1}T_{2}}{T_{1}} = \frac{1.5 atm*(67 + 273)K}{300 K} = 1.7 atm  

Por lo tanto, si en el transcurso de un viaje las ruedas alcanzan una temperatura de 67 ºC, el neumático soportará una presión de 1.7 atm.

Espero que te sea de utilidad!

4 0
3 years ago
__________ is when a person becomes less sensitive to a drug. A. Tolerance B. Craving C. Addiction D. Dependence
Luden [163]
A) Tolerance

Tolerance is developed after using a drug repeatedly, so the body adapts to it. Because of that, people who develop a tolerance would then need to use more of that drug to get the same effect.
4 0
3 years ago
Which list shows the development of atomic models in chronological order?
ratelena [41]
The correct option is PLUM PUDDING, SOLAR SYSTEM, ELECTRON CLOUD. 
J. J Thompson was the scientist who proposed the plum pudding theory of atomic model. Neil Borh was the one who developed the solar system model of atomic theory while the electron cloud model of atomic theory that is presently been used was developed by an Australian scientist called Erwin Schrodinger.<span />
5 0
3 years ago
Read 2 more answers
Other questions:
  • - The school zone in front of your school has a posted speed limit of 25 mi/h, which is about 11 m/s. Let's
    11·1 answer
  • What are some advantages of using the graphical method of vector resolution?
    12·1 answer
  • Thinking about the winter we missed out on this year. Calvin and his tiger go sledding down a snowy hill. There is friction betw
    9·1 answer
  • Gel electrophoresis is a technique used to separate nucleic acids by their _______.
    15·1 answer
  • A test rocket is launched vertically from ground level (y=0), at time t=0.0s. The rocket engine provides constant upward acceler
    12·1 answer
  • Determina el trabajo realizado al desplazar un bloque 3 m sobre una superficie horizontal, si se desprecia la fricción y la fuer
    10·1 answer
  • In Europe, gas cost approximately €0.98 per liter. How many dollars($) per gallon is this? ​ using a factor method
    5·1 answer
  • A 8.5 kg brick is dropped onto a 6.5 kg toy truck, which is moving across a level floor at 0.50 m/s. With what velocity do the t
    13·1 answer
  • Click to review the online content. Then answer the question(s) below, using complete sentences. Scroll down to view additional
    11·1 answer
  • explain the fleming left-hand rule with the diagram and what will the direction of the induced current in the figure if the magn
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!