so as we know potential energy is stored energy which is the top of the roller coaster when you increase the pull of gravity you will increase potential energy and kinetic energy is a theory that states that particles of matter are always in motion. and that the amount of motion depends on the amount of energy in the particles so for short kinetic energy is energy in motion which is the roller coaster when its moving. mechanical energy is the same thing energy in motion such as a moving vehicle which is still the roller coaster when its moving. conservation of energy from the roller coaster is not destroyed nor created the energy changes form.
so the potential energy is stored in the top of the roller coaster. kinetic energy is when the roller coaster is in motion same thing for mechanical and conservation is the energy that is being released from the roller coaster is neither destroyed nor created.
i hope this makes sense XD
Answer:
a. Endothermic
b. 26.37kJ/mol
Explanation:
a. As we can see, the temperature of the water is decreasing when the reaction is occurring, that means the reaction is absorbing heat and is endothermic
b. To find the enthalpy we must find the change in heat when 12.1g of KCl are dissolved. Using the equation:
Q = -m*ΔT*C
<em>Where Q is change in heat</em>
<em>m the mass of solution (250g + 12.1g = 262.1g)</em>
<em>ΔT is change in heat (17.1°C - 21.0°C = -3.9°C)</em>
<em>And C is specific heat of the solution (4.184J/g°C assuming is the same than the specific heat of water).</em>
<em />
Replacing:
Q = -262.1g*-3.9°C*4.184J/g°C
Q = 4277J = 4.28kJ
As reaction enthalpy is the change in heat per mole of reaction, we must find the moles of 12.1g of KCl:
<em>Moles KCl -Molar mass: 74.55g/mol-:</em>
12.1g KCl * (1 mol / 74.55g) = 0.1623 moles KCl
The reaction enthalpy us:
4.28kJ / 0.1623mol = }
<h3>26.37kJ/mol</h3>
<em />
<span>An unbalanced force acting on a body at rest will change the motion of the body. The of motion is measured by its momentum.</span>
E. 0.42 meters / second
Since you are finding the average speed, you don't need to factor in all the stops Mary makes on her way to her final destination. Add the total distance she walked ( 80 + 125 + 45 ) and divide it by the amount of time IN SECONDS that it took for her to do this. Since the time given is in minutes, simply multiply the number of minutes ( 10 ) by 60 ( the amount of seconds in a minute ). Then divide the total number of meters walked by the total amount of seconds it took to walk, and you will get your average speed.
( Also, this is a Physics question, not Chemistry :D )