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
a cell phone uses 3.0V battery. the circuit board needs a 0.05 A current. what size resistor is needed to generate this current
san4es73 [151]

Answer:

60 Ohms

Explanation:

Ohms law states that the voltage in the circuit is directly proportional to the current through the circuit components and expressed as

V=IR

Where V is the voltage, I is current and R is resistance

Making R the subject of the formula then

R=\frac {V}{I}

Substituting 3.0V for V and 0.05 A for I then

R=\frac {3}{0.05}=60.0

Therefore, resistance is 60.0 Ohms

7 0
3 years ago
What is one benefit of lifelong physical activity?
kvasek [131]
The answer would be C
5 0
3 years ago
A turntable with a moment of inertia of 7.2 × − ⋅ rotates freely with an angular speed of 6.5 ⁄ . Riding on the rim of the turnt
irina1246 [14]

Answer:

turntable with a moment of inertia of 7.2 × − ⋅ rotates freely with an angular speed of 6.5 ⁄ . Riding on the rim of the turntable, 2 from the center, is a hamster. When the hamster walks to the center of the turntable, the angular speed of the turntable becomes ⁄. What is the mass of hamster?

Explanation:

6 0
2 years ago
Which statements describe a fully charged capacitor? Check all that apply.
Oksanka [162]
Well, first of all, there's no such thing as "fully charged" for a capacitor.

A capacitor has a "maximum working voltage", because of mechanical
or chemical reasons, just like a car has a maximum safe speed.  But
anywhere below that, cars and capacitors do their jobs just fine, without
any risk of failing.

So we have a capacitor that has some charge on it, and therefore some
voltage across it.  From the list of choices above . . .

<span>-- Both plates have the same amount of charge.
Yes.  And both plates have opposite TYPES of charge.
One plate is loaded with electrons and is negatively charged.
The other plate is missing electrons and is positively charged.

-- There is a potential difference between the plates.
Yes.  That's the "voltage" mentioned earlier.
It's a measure of how badly the extra electrons want to jump
from the negative plate to the positive plate.

-- Electric potential energy is stored.
Yes.  It's the energy that had to be put into the capacitor
to move electrons away from one plate and cram them
onto the other plate.


</span>
4 0
3 years ago
Read 2 more answers
A 25,000 kg traveling east collides with a 2,000 kg truck standing still on the tracks. After the collision the train and truck
Elis [28]

Answer:

24.084 m/s

Explanation:

From the law of conservation of linear momentum

Total momentum before collision equals to the total momentum after collision

Since momentum=mv where m is mass and v is velocity

M_{truck}V_{truck}=V_{common}*(M_{truck} +M_{standing}) where M_{truck} is the mass of the truck, V_{truck} is velocity of the truck, V_{common} is the common velocity of moving and standing truck after collision and M_{standing} is the mass of the standing truck

Making V_{truck} the subject we obtain

V_{truck}=\frac { V_{common}*(M_{truck} +M_{standing})}{M_{truck}}

Substituting M_{truck} as 25000 Kg, V_{common} as 22.3 m/s, M_{standing} as 2000 Kg we obtain

V_{truck}=\frac { 22.3 m/s *(25000 Kg +2000 Kg)}{25000}= 24.084 m/s

Therefore, assuming no friction and considering that after collision they still move eastwards hence common velocity and initial truck velocities are positive

The truck was moving at 24.084 m/s

3 0
3 years ago
Other questions:
  • A glider of mass 0.240 kg is on a frictionless, horizontal track, attached to a horizontal spring of force constant 6.00 N/m. In
    14·1 answer
  • How many innings are in a regulation softball game?
    10·1 answer
  • Gravity is a force between any two objects with mass wht doesn’t a person feel a gravitational force between them herself and an
    5·1 answer
  • Constants Canada geese migrate essentially along a north-south direction for well over a thousand kilometers in some cases, trav
    10·1 answer
  • What is unit of pressure?why is it called a derived unit ? give reasons​
    10·1 answer
  • Can anyone help me please​
    7·1 answer
  • 4. What is the momentum of a 70 kg object traveling at 20 m/s?
    7·1 answer
  • Three collisions are elastic and three are inelastic. Determine which collision type took place for each collision. Support your
    6·1 answer
  • An 85 kg man stands in a very strong wind moving at 15 m/s at torso height. As you know, he will need to lean in to the wind, an
    14·1 answer
  • Match up the following set of words with their definitions.
    7·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!