Answer:
As the temperature of materials increase, the objects find a phenomenon called change of phase.
This means that if you give enough heat to a liquid, this can change of state from liquid state to gas state (the water evaporates)
So the water in the pan reaches the evaporation temperature (around 100°C) and it starts to evaporate, this is why the water on the outside begins to "dry"
Answer:
The speed of water must be expelled at 6.06 m/s
Explanation:
Neglecting any drag effects of the surrounding water we can assume the linear momentum in this case is conserves, that is, the total initial momentum of the octopus and the water kept in it cavity should be equal to the total final linear momentum. That's known as conservation of momentum, mathematically expressed as:

with Pi the total initial momentum and Pf the final total momentum. The total momentum is the sum of the momentums of the individual objects, in our case the octopus and the mass of water that will be expelled:

with Po the momentum of the octopus and Pw the momentum of expelled water. Linear momentum is defined as mass times velocity:

Note that initially the octopus has the water in its cavity and both are at rest before it sees the predator so
:

We should find the final velocity of water if the final velocity of the octopus is 2.70 m/s, solving for
:


The minus sign indicates the velocity of the water is opposite the velocity of the octopus.
Work = Force times Distance
W = Fd
Given W = 750J, F = 125N;
750 = 125d
Solving for d:
d = 750/125
d = 6
The box moved a distance of 6 meters.
Answer:
Explanation:
Let x ft be used to make square and 2-x ft be used to make equilateral triangle.
each side of square = x/4
area of square = ( x /4 )²
Each side of triangle
= (2-x) /3
Area of triangle = 1/2 (2-x)²/9 sin 60
= √3 / 36 x (2-x)²
Total area
A = ( x /4 )² +√3 / 36 (2-x)²
For maximum area
dA/dx = 0
1/16( 2x ) -√3 / 36 x2(2-x) = 0
x / 8 - √3(2-x)/ 18 = 0
x / 8 - √3/9 + √3/18 x = 0
x ( 1/8 + √3/18 ) = √3/9
x(.125 +.096 ) = .192
x = .868 ft
Answer: the magnetic wave will travel out of the screen.
Explanation:
Electric field direction is perpendicular to the magnetic field direction. Both are also perpendicular to the direction of the particles.
Using right hand rule to solve this problem,
This pointed finger depicts the electric field direction which the curly fingers depict the direction of the magnetic field. The pointed thumb will depict the direction in which the wave travel. Which is out of the screen.