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
antoniya [11.8K]
2 years ago
5

Which best describes friction?

Physics
1 answer:
tangare [24]2 years ago
5 0

Answer:

a constabt force that acts on object that rub together

Explanation:

It is because Friction is the rubbing of one body against another body

You might be interested in
Leila is building an aluminum-roofed shed in her backyard to store her garden tools.The flat roof will measure 2.0 x 3.0m in are
IrinaK [193]
Answer: 0.0138 m^2  = 138 cm^2

Explanation:

The thermal expansion is the term use for the physical phenomena of dilation of the objects when they are exposed to changes in temperature.

The objects dilate when they are heated and contract when they are cooled.

The dilation is proportional to the change in temperatur.

For linear dilation, the proportionality constant is called linear dilation coefficient of the materials, it is named α and is measured in °C ^-1.

ΔL = α * Lo * ΔT, which means that the dilation (or contraction) is proportional to the product of the original length (Lo) and the change of temperature (ΔT).

There is also superficial dilation, for which the dilation is:

ΔA = β * Ao * ΔT, which means that the superficial dilation (or contraction) is proportional to the product of the original area (Ao) and the change of temperature (ΔT).

It is very interesting and important to solve problems that β = 2α, because regularly you will find the values of α for different materials and so, you just to multiply it times 2 to use β.

For this problem:

- Original area, Ao = area of the flat roof at - 10°C = 2.0m * 3.0m = 6.0 m^2.
- α for aluminum = 24 * 10^ -6 °C^-1.
- ΔT = 38°C - (-10°C) = 48°C

So, ΔA = 6.0m^2 * (2 * 24*10^-6 °C&-1) * 48°C = 0.0138 m^2

And that is the area that should stick out in summer to fit the structure during cold winter nights.

You can pass that number to cm^2 to grasp better the idea of this size:

0.0138 m^2 * (100 cm)^2 / m^2 = 138 cm^2




3 0
3 years ago
Can an object with constant acceleration reverse its direction of travel? Can it reverse its direction twice? Explain.
Neko [114]

Answer:yes

Explanation:The constan acceleration means that it wont stop moving but if you kick it a different direction then it will change direction

6 0
3 years ago
An echo is not heard in a small room.why ? give reason<br>​
JulsSmile [24]

Answer:

They can't hear an echo in small room because in it the sound can't be reflected back. For an echo of a sound to be heard,the minimum distance between the source of sound and the walls of the room should be 17.2 m.

hopw it helps

7 0
3 years ago
Read 2 more answers
Is condensation adding thermal energy
Anna35 [415]
I believe it is, since the heat causes the water to evaporate and cause condensation,
3 0
3 years ago
You can carry a 50 N weight up a flight of stairs that is 3 m high in 10 s. Then you carry 40 N up two flights of stairs in 20 s
d1i1m1o1n [39]
You can do 50 and 10 and carry the 30 and it would be in the same power so you’ll have the same energy
5 0
3 years ago
Other questions:
  • Waves that make up the visible part of the electromagnetic spectrum have
    12·1 answer
  • Carbon show some unique property name them name them​
    14·1 answer
  • To model this process, assume two charged spherical conductors are connected by a long conducting wire and a 1.20-mC charge is p
    13·1 answer
  • An energy plant produces an output potential of 1500 kV and serves a city 143 km away. A high-voltage transmission line carries
    8·1 answer
  • Suppose you are driving in a convertible with the top down at constant speed. You point a rifle straight upward and fire it. In
    12·1 answer
  • A 4.2-m-diameter merry-go-round is rotating freely with an angular velocity of 0.79 rad/s . Its total moment of inertia is 1790
    9·1 answer
  • #37, what is this answer ?
    15·1 answer
  • A lightbulb has a power rating of 6.75 W and draws a current of 0.75 A when connected to a battery.
    14·1 answer
  • You are walking on a moving walkway in the airport. The length of the walkway is 59.1 m. If your velocity relative to the walkwa
    14·1 answer
  • A taxi hurries with a constant speed of 60 miles per hour. How long will it take to travel a distance of 130 miles
    6·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!