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
Papessa [141]
3 years ago
7

How long does it take the Sun to melt a block of ice at 0∘C with a flat horizontal area 1.0 m2 and thickness 2.0 cm ? Assume tha

t the Sun's rays make an angle of 30 ∘ with the vertical and that the emissivity of ice is 0.050.
Physics
1 answer:
Savatey [412]3 years ago
4 0
The answer is c don't ask why it just is
You might be interested in
_ acceleration occurs when an object speeds up.<br> Answer<br> Positive
Nina [5.8K]

_ acceleration occurs when an object speeds up.

Answer

Positive

6 0
3 years ago
Read 2 more answers
When a board with a box on it is slowly tilted to larger and larger angle, common experience shows that the box will at some poi
eimsori [14]

Answer: The force of kinetic friction is smaller than that of static friction, but F_g  remains the same.

Explanation:

The situation is same as when a book is pushed with an increasing force on a table; When the force is low, book doesn't move, until that under a given force starts moving, and then it goes on movement even if the force decreases a bit.

The physical explanation for this, that friction force adopts any value needed to avoid to move the object, till a limit value is achieved, called static friction force, equal to the normal force times the static friction coefficient.

Once in movement, the kinetic friction coefficient replaces the static one , and  in general is lower than the static one, so the force diminishes.

In the case of the box sliding down the board, the force that tries to move the object down the board, is the component of the weight parallel to the board, that can be showed that being equal to the weight times the sinus of the angle of the board with the horizontal, as follows:

F_g = m g sin θ

When θ increases, F_g does the same, so friction force always has the same magnitude than F_g (but opposite direction) so the box doesn't move, till that θ takes a value that produces a F_g equal to static friction force.

Beyond this limit angle, F_g (remaining the same for a given angle) is greater than the kinetic friction force, and the box slides.

In the limit, when θ=90º, sin θ =1⇒ F_g = mg, so the object is in free fall.

6 0
3 years ago
How to delete question​
Marrrta [24]
Oh your from the other question you made I just saw it LOL.
But heres the answer click the 3 dots on the question you made or you can ask a Moderator or Administrator to remove your question with a reason.
6 0
3 years ago
Read 2 more answers
One of the world's largest Ferris wheels, the Cosmo Clock 21 with a radius of 50.0 m is located in Yokohama City, Japan. Each of
STatiana [176]

Answer:

a = 0.55 m / s²

Explanation:

The centripetal acceleration is given by the relation

         a = v² / r

angular and linear velocities are related

         v = w r

we substitute

          a = w² r

In the exercise they indicate the angular velocity w = 1 rev/min, let's reduce to the SI system

          w = 1 rev / min (2pi rad / 1rev) (1min / 60s) = 0.105 rad/ s

let's calculate

          a = 0.105² 50.0

          a = 0.55 m / s²

4 0
3 years ago
The x-component of vector R is Rx = −28.2 units and its y-component is Ry = 19.6 units. What are its magnitude and direction? Gi
ikadub [295]

Answer:

Explanation:

Rx = -28.2 units

Ry = 19.6 units

magnitude of R = √  [( - 28.2 )² + ( 19.6 ) ]

= √ ( 795.24 + 384.16 )

= 34.34 units

If θ  be the angle measured counterclockwise from the +x-direction

Tanθ = 19.6 / - 28.2 = -0.695

θ = 180 - 34.8

= 145.2° .

7 0
3 years ago
Other questions:
  • Which of the following is a poor conductor of heat?. A. silver. B. aluminum. C. gold. D. copper. E. air. How can you tell the di
    14·2 answers
  • A car travelled a distance of 348 km in 6.0 hours. What was it’s speed in (a) km/h and (b) m/sec?
    12·1 answer
  • Protons and ____ have electric charge?
    5·2 answers
  • To estimate the distance in kilometers of a flash of lightning, count the number of seconds between seeing the flash and hearing
    11·1 answer
  • 8) What kind of circulation carries blood to all organs and systems?
    14·2 answers
  • A 762 kg car experiences a braking force of 9045 N and skids to a stop in 4.3 seconds. What is the speed of the car just before
    8·1 answer
  • A high increase his speed from 3.2 m/ s to 5.6m/s during in interval. What is his acceleration that time
    9·1 answer
  • What type of circuit is pictured?<br> O Parallel Circuit<br> Series Circuit
    13·2 answers
  • How does fabric softener help prevent static electricity?
    13·1 answer
  • How much work is done when a hoist lifts a 210-kg rock to a height of 3 m? (Use 9.8 m/s2 for the acceleration due to gravity.)
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!