Decreases, stays the same, increases.
The volume decreases because as air is cooled, the individual molecules collectively possess less kinetic energy and the distances between them decrease, thus leading to a decrease in the volume they occupy at a certain pressure (please note that my answer only holds under constant pressure; air, as a gas, doesn't actually have a definite volume).
The mass stays the same because physical processes do not create or destroy matter. The law of conservation of mass is obeyed. You're only cooling the air, not adding more air molecules.
The density decreases because as the volume decreases and mass stays the same, you have the same mass occupying a smaller volume. Density is mass divided by volume, so as mass is held constant and volume decreases, density increases.
Mechanical energy is made when something is moved. The energy that is moving is kinetic. And potential energy is stored energy. Mechanical energy can be used to store energy and to cause moving energy. For instance: a slingshot. Pulling back the band creates potential energy and releasing it creates kinetic energy.
Answer:
Explanation:
It is given that,
Length of the wire, L = 0.6 m
Current flowing inside the wire, I = 2 A
Uniform magnetic field, B = 0.3 T
Force experienced by the wire in the magnetic field, F = 0.18 N
To find,
The angle made by the wire with the magnetic field.
Solve,
We know that the magnetic force acting on the wire inside the magnetic field is given by :
Therefore, the wire makes an angle of 30 degrees with respect to magnetic field.
Answer:A
Explanation:matter normally occurs in three phases;solid, liquid and gases. They may change from one phase to another due to temperature difference.
The molecules that makes up solids are held together by bonds. When heat is added,the molecules begin to move as a result,the bonds break and it turns to liquid.this process is called melting. The reverse of melting is freezing.
Liquid are made up of molecules that moves more freely than solids. When heat is added to liquid,the molecules gain more energy and begins to move faster. This causes them to turn to gases.
This process is called evaporation. It occurs at different temperature for different substances.
The particles of gases move more faster and are separated by large distances. A gas can change back to a liquid through condensation.
Answer:
Explanation:
Even though the minimum temperature is more than the freezing point, Frost was observed on the ground because the ground will cool rapidly as cool air tends to move towards the ground, the temperature of the ground is lower than the atmosphere a few feet above it.
As the thermometer is kept some feet above the ground so ground temperature may be lower than the minimum recorded temperature.
