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
Inessa05 [86]
3 years ago
10

When water in a lake freezes, the ice that forms floats on top of any water that is still liquid. Why does the ice float?

Physics
1 answer:
ddd [48]3 years ago
5 0

Answer:

it floats because the lake is cold at that moment so when part of the lake freezes it still remains solid and floats because of the lake and the surrounding of the lake is still cold

You might be interested in
Science cannot be used to answer questions about _____.
aksik [14]
Science cannot be used to answer questions about Moral judgements
8 0
3 years ago
Read 2 more answers
Spiderman, whose mass is 70.0 kg, is dangling on the free end of a 12.2-m-long rope, the other end of which is fixed to a tree l
Lana71 [14]

Answer:

U = -3978.8 J

Explanation:

The work of the gravitational force U just depends of the heigth and is calculated as:

U = -mgh

Where m is the mass, g is the gravitational acceleration and h the alture.

for calculate the alture we will use the following equation:

h = L-Lcos(θ)

Where L is the large of the rope and θ is the angle.

Replacing data:

h = 12.2-12.2cos(58.4)

h = 5.8 m

Finally U is equal to:

U = -70(9.8)(5.8)

U = -3,978.8 J

5 0
3 years ago
A 0.4-kg toy train car moving forward at 3 m/s collides with and sticks to a 0.8–kg toy car that is traveling in the opposite di
Gemiola [76]

Hey there!

Seems like you're looking for the size and direction to the final velocity of the two cars. To find it, you must solve it like this.

0.4 kg(3 m/s) + 0.8kg(–2 m/s) = 1.2 kg m/s -1.6 kg m/s = –0.4 kg m/s

–0.4 kg m/s = 1.2 kg(v) = (–0.4 kg m/s)/(1.2 kg) = v = –0.33 m/s


So, the cars are traveling at -0.33 m/s in the direction of the second car.


Hope this helps


<em>Tobey</em>

4 0
3 years ago
A light ray incident from medium 1 to medium 2, where n1&gt;n2. When the incident angle exceed the critical angle ac, the refrac
vovikov84 [41]

Explanation:

(a)

Critical angle is the angle at the angle of refraction is 90°. After the critical angle, no refraction takes place.

Using Snell's law as:

n_1\times {sin\theta_i}={n_2}\times{sin\theta_r}

Where,  

{\theta_i}  is the angle of incidence

{\theta_r} is the angle of refraction = 90°

{n_2} is the refractive index of the refraction medium

{n_1} is the refractive index of the incidence medium

Thus,

n_1\times {sin\ \theta_{critical}}={n_2}\times{sin\ 90^0}

The formula for the calculation of critical angle is:

{sin\theta_{critical}}=\frac {n_2}{n_1}

Where,  

{\theta_{critical}} is the critical angle

(b)

No it cannot occur. It only occur when the light ray bends away from the normal which means that when it travels from denser to rarer medium.

7 0
3 years ago
Answer this please nowww
Viefleur [7K]
(3) The frictional force exerted by the floor on the box
4 0
3 years ago
Other questions:
  • Strength of the electric force imagine two 1.0-g bags of protons, one at the earth's north pole and the other at the south pole.
    14·1 answer
  • The slope of a distance vs. time graph is a measurement called
    10·1 answer
  • Do you support trucks are identical each box loaded on the truck has the same mask choose the truck that has the greatest force
    13·1 answer
  • Ganymede is one of the many moons of jupiter. it is nearly a sperical in shape. it is larger than the planet mercury and slightl
    6·1 answer
  • A 3-cm high object is in front of a thin lens. The object distance is 4 cm and the image distance is –8 cm. (a) What is the foca
    7·1 answer
  • A student pushed a 100 N bicycle over a distance of 15 m in 5 s. calculate the power generated.
    8·1 answer
  • What would the products of a double-replacement reaction between Na2S
    9·1 answer
  • What energy store is in the torch<br>BEFORE it gets switched on?​
    10·1 answer
  • Can you hear it? In the cartoon space rocket, why do you think you would not be able to hear the whoosh of the rocket engine in
    11·1 answer
  • If the masses are not changed, but the distance of separation is tripled, what happens to the for
    7·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!