1. Changing from solid to a liquid is called melting / fusion and happen
at the melting/ fusion point.
Reason: melting point is a temperature at which a solid melt and converts into liquid by providing heat.
2. Changing from liquid to gas is called evaporation/boiling and happens at the evaporation/boiling point.
Reason. Evaporation is a process in which molecules from surface of liquid convert into gas.
3. Changing from a gas to a liquid is called condensation and happens at the condensation point.
Reason : In condensation process gas particles converts into liquid droplets.
4. Changing from liquid to a solid is called freezing and happens at the freezing point.
Reason : Freezing is a process that convert liquid into soilid state by decreasing temperature of that specific liquid,
Answer:
The greatest force of gravity on the ball will occur at the point when the ball is near to hit the ground
Explanation:
We know that the earth's center attracts everything towards its center with an acceleration of 9.8 m/s² so it simply means that the change in velocity must occur to produce acceleration. When the ball comes towards the earth, its speed continuously increases and it is at maximum level when it is about to hit the ground so this is the point where gravitational force is maximum.
I hope this helps ^_^
It’s like the force put against something or someone✨
The correct answer for the statement “All the scientific
theories used to explain the formation of the solar system are non-testable”. The
answers outdated, imaginative and unacceptable are wrong. These theories are
not proven and yet are not tested due to the complexity.
<span>The first thing to do here is to figure out how many joules of energy would be produced by your lightbulb in one hour.
As you can see, the conversion factor to use here is
#"1 W" = "1 J"/"1 s"#
This is basically a reminder of the fact that the watt, a unit of power, is defined as an energy of one joule delivered in one second.
Since one hour is known to have #60# minutes, i.e. #60 xx "60 s"#, you will have
#60 xx 60 color(red)(cancel(color(black)("s"))) * "140 J"/(1color(red)(cancel(color(black)("s")))) = "504000 J" = "504 kJ"#
Your next step here will be to use the enthalpy of vaporization of water to figure out how many grams of water would be evaporated by that much heat.
#DeltaH_"vap" = "44.66 kJ mol"^(-1)#
Convert this to kilojoules per gram by using water's molar mass
#44.66 "kJ"/color(red)(cancel(color(black)("mol"))) * (1color(red)(cancel(color(black)("mole H"_2"O"))))/("18.015 g") = "2.479 kJ g"^(-1)#
This means that the mass of water that can be evaporated by #"504 kJ"# of heat will be
#504color(red)(cancel(color(black)("kJ"))) * ("1 g H"_2"O")/(2.497color(red)(cancel(color(black)("kJ")))) = "201.8 g"#
Now, assuming that the sweat is pure water, you can approximate its density to be equal to #"1.0 g mL"^(-1)#. This means that the volume of water that can be evaporated will be
#201.8 color(red)(cancel(color(black)("g"))) * "1 mL"/(1.0color(red)(cancel(color(black)("g")))) = color(green)(bar(ul(|color(white)(a/a)color(black)(2.0 * 10^2 "mL")color(white)(a/a)|)))#
The answer is rounded to two</span>
