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
Amanda [17]
3 years ago
14

Two trains are blowing their whistles. The first train is stationary, and the

Physics
1 answer:
Liono4ka [1.6K]3 years ago
3 0

Answer:

A I think

Pls Mark Brainiest, I'm trying to become Virtuoso

You might be interested in
What is newton's 3rd law of physics ​
ValentinkaMS [17]

Answer:

His third law states that for every action (force) in nature there is an equal and opposite reaction. In other words, if object A exerts a force on object B, then object B also exerts an equal and opposite force on object A.

4 0
3 years ago
A car of mass m goes around a banked curve of radius r with speed v. If the road is frictionless due to ice, the car can still n
Sholpan [36]

Answer:

horizontal component of normal force is equal to the centripetal force on the car

Explanation:

As the car is moving with uniform speed in circle then the force required to move in the circle is towards the center of the circle

This force is due to friction force when car is moving in circle with uniform speed

Now it is given that car is moving on the ice surface such that the friction force is zero now

so here we can say that centripetal force is due to component of the normal force which is due to banked road

Now we have

N sin\theta = \frac{mv^2}{R}

N cos\theta = mg

so we have

v = \sqrt{Rg tan\theta}

so this is horizontal component of normal force is equal to the centripetal force on the car

5 0
3 years ago
Will give brainliest
NNADVOKAT [17]

I love science! if you need any more help let me know i cant guarantee i can help but i will try!

The correct answer is  "Some substances must be dissolved in water before they can be used".  

5 0
3 years ago
In which of the two situations described is more energy transferred?
Furkat [3]

Answer:

More energy is transferred in situation A

Explanation:

Each of the situations are analyzed as follows;

Situation A

The temperature of the cup of hot chocolate = 40 °C

The temperature of the interior of the freezer in which the chocolate is placed = -20 °C

We note that at 0°C, the water in the chocolate freezes

The energy transferred by the chocolate to the freezer before freezing is given approximately as follows;

E₁ = m×c₁×ΔT₁

Where;

m = The mass of the chocolate

c₁ = The specific heat capacity of water = 4.184 kJ/(kg·K)

ΔT₁ = The change in temperature from 40 °C to 0°C

Therefore, we have;

E₁ = m×4.184×(40 - 0) = 167.360·m kJ

The heat the coffee gives to turn to ice is given as follows;

E₂ = m·H_f

Where;

H_f = The latent heat of fusion = 334 kJ/kg

∴ E₂ = m × 334 kJ/kg = 334·m kJ

The heat required to cool the frozen ice to -20 °C is given as follows;

E₃ = m·c₂·ΔT₂

Where;

c₂ = The specific heat capacity of ice = 2.108 kJ/(kg·K)

Therefore, we have;

E₃ = m × 2.108 ×(0 - (-20)) = 42.16

E₃ = 42.16·m kJ/(kg·K)

The total heat transferred = (167.360 + 334 + 42.16)·m kJ/(kg·K) = 543.52·m kJ/(kg·K)

Situation B

The temperature of the cup of hot chocolate = 90 °C

The temperature of the room in which the chocolate is placed = 25 °C

The heat transferred by the hot cup of coffee, E, is given as follows;

E = m×4.184×(90 - 25) = 271.96

∴ E = 271.96 kJ/(kg·K)

Therefore, the total heat transferred in situation A is approximately twice the heat transferred in situation B and is therefore more than the heat transferred in situation B

Energy transferred in situation A = 543.52 kJ/(kg·K)

Energy transferred in situation B = 271.96 kJ/(kg·K)

Energy transferred in situation A ≈ 2 × Energy transferred in situation B

∴ Energy transferred in situation A > Energy transferred in situation B.

3 0
2 years ago
When determining the number of significant digits in a measurement,
Black_prince [1.1K]
B) All nonzero digits are significant.
6 0
3 years ago
Read 2 more answers
Other questions:
  • How are humans contributing to climate change?
    7·1 answer
  • An object is placed 10 cm in front of a diverging mirror. What is the focal length of the mirror if the image appears 2 cm behin
    7·1 answer
  • A jet airplane flying from Darwin, Australia, has an air speed of 260 m/s in a direction 5.0º south of west. It is in the jet st
    13·1 answer
  • Two passenger cars, car A and car B, of the same weight are put to a 30 mph head-on crash test. In the test, cars are pulled for
    15·1 answer
  • When a chemical reaction occurs with only one substance, what happens to the atoms of that substance?
    7·2 answers
  • Suppose Galileo dropped a lead ball (100 kilograms) and a glass ball (1 kilogram) from the Leaning Tower of Pisa. Which one hit
    8·1 answer
  • Which of the following has the same unit as the moment of force?
    8·2 answers
  • A battery-powered lawn mower has a mass of 48.0 kg. If the net external force on
    11·1 answer
  • Help, please. I am not sure what to do.
    13·1 answer
  • Remember KE=M*V2/2…
 A model airplane moves twice as fast as another identical model airplane. Compared with the kinetic energy
    13·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!