Answer:
Explained
Explanation:
Resistance R in a current flow through an object is given by
ρ = resistivity of the material
L= length of the object
A= area of cross section
clearly resistance is directly dependent on length of the object.This means greater the length larger will be resistance to current.
thermal resistance R_th is given by
L= length of the object
A= area of cross section
K = Conductivity of the material
thermal resistance is also is directly dependent on length of the object.This means greater the length larger will be resistance to current.
The answer is evolution. When a specifies evolves over time they change and adapt to their environment.
Explanation:
Water does expand with heat (and contract with cooling), but the amount of expansion is pretty small. So when you boil a can filled with water and seal it, the water will contract slightly as it cools. The can may kink slightly, but that will be it. Actually, most likely the only things you will be able to see is then top and bottom will be sucked in and go concave. Just like a commercial can of beans.
Now if you have a can with a little water and a big air space, things are completely different.
As the water boils, water vapour is given off. Steam. Let it boils for a minute just to make sure (nearly) all the air is expelled and the can is filled with steam.
Now when you put the lid on and cool the can, that steam condenses back to water, and goes from filling the can to a few drops of water. The can is now filled (if that is the right word) with a near vacuum, The air pressure, 15 lbs/square inch, will be pressing on every surface of the can, with nothing inside the can to resist it.
The can will crumple before your eyes.
Answer:
2/3
Explanation:
In the case shown above, the result 2/3 is directly related to the fact that the speed of the rocket is proportional to the ratio between the mass of the fluid and the mass of the rocket.
In the case shown in the question above, the momentum will happen due to the influence of the fluid that is in the rocket, which is proportional to the mass and speed of the same rocket. If we consider the constant speed, this will result in an increase in the momentum of the fluid. Based on this and considering that rocket and fluid has momentum in opposite directions we can make the following calculation:
Rocket speed = rocket momentum / rocket mass.
As we saw in the question above, the mass of the rocket is three times greater than that of the rocket in the video. For this reason, we can conclude that the calculation should be done with the rocket in its initial state and another calculation with its final state:
Initial state: Speed = rocket momentum / rocket mass.
Final state: Speed = 2 rocket momentum / 3 rocket mass. -------------> 2/3
