Energy & Laws of Thermo
Potential Energy
Kinetic Energy/TME
Efficiency/Energy Conversions
Bonus
100
Define Energy:
Energy is the ability to do work
100
Define Potential energy and list the four different types of PE.
Potential Energy: the stored energy that is capable of being transformed into other forms of energy that can do work.
1. Gravitational Pot. Energy
2. Chemical Pot. Energy
3. Nuclear Pot. Energy
4. Elastic Pot. Energy
100
Define Kinetic energy in words & provide the SI units
Kinetic Energy is the Energy given to an object, the energy of motion, measured in Joules (J).
100
What is the formula for Efficiency?
Are there units for efficiency?
What is:
Efficiency = Output Energy ÷ Input Energy x 100%
No, since efficiency is a ratio it is expressed as a percentage.
100
What is this song called? & Who sings it?
https://drive.google.com/file/d/19Px_rRsSGsmD2t3UjGLlxrnWpBWufHZQ/view?usp=drive_link
Bonus 100 points if you can tell me what decade it came out
Just the Two of Us - Tiktok has appropriated another Soul anthem :(
The Kings: Bill Withers & Grover Washington Jr.
Released: 1980
200
What is the difference between thermal energy & heat?
What is the definition of Thermal Energy?
Thermal Energy & Heat are the same thing.
Heat/Thermal Energy: transfer of thermal energy from one object to another
200
In an Ideal world, Ep is Equal to ________
This is because in the absence of other forces: __________________________________________________________
In an Ideal world, Ep is Equal to Ek
In the absence of other forces: all the Ep in a system is converted into Ek
200
What two quantities affect an object's Kinetic Energy? (Hint Ping Pong Balls, Baseballs)
The mass & velocity/speed of an object.
If the same amount of work is applied, the heavier & faster an object is moving, the more kinetic energy it has.
The lighter and slower an object is moving, the less kinetic energy it has!
*the logic for this question is that the only different between velocity and speed is a direction. Therefore, Ek can be calculated using both a speed or velocity value as long as we remove the direction!
200
How does a furnace work in terms of energy conversions?
Propane/natural gas is burned and produces heat
The heat exchanger (coil) then absorbs the heat & heats up. (Energy transfer)
The air in our home is blown over the heat exchanger, which warms up the air. (Energy transfer)
Finally, the air is distributed through the air ducts to each part of the house!
200
What country in the world has the most lakes?
Canada, with 879,800 Lakes!
300
Name the centre of an atom.
Name the process that happens inside the sun that allows it to heat our galaxy.
What is the nucleus?
What are nuclear fusions? (the bonding of two atomic nuclei to which produces energy)
300
How far would you have to lift a 1.2kg book to give it 40.0 J of gravitational potential energy? (Pay attention to significant digits)
Eg = mgh --> h = (Eg) ÷ (mg)
h = (40.0 J) ÷ (1.2 kg x 9.81m/s2)
h = 3.397893306 m --> ~3.4 m
300
A train with a mass of 1500 kg is moving at a speed of 26 m/s. What is the kinetic energy of the train (In Joules)?
Ek = (mv2) ÷ 2
Ek = (1500kg) x (262 m/s) --> (1500kg) x (676 m/s) / 2
Ek = 507000 J --> ~5.1 x 105 J
300
An ideal lightbulb produces 879 kJ of energy (fake lightbulb). The voltmeter you used on your bedroom lightbulb says it's emitting 327000 J of energy.
What is the efficiency of your lightbulb?
Efficiency = Output ÷ Input x 100%
327000 J ÷ 1000 J = 327 kJ
Efficiency = 327 kJ ÷ 879 kJ x 100% = 37.201%
Efficiency = The lightbulb is ~37.2 % efficient.
300
Name as many countries you can that start with P
100 points per country
- Pakistan
- Palau
- Panama
- Papua New Guinea
- Paraguay
- Peru
- Philippines
- Poland
- Portugal
- Puerto Rico
- Palestine *
400
What are the three types of clues we can see in a system that serves as evidence that the system contains energy? (Hint: think about an ice cube)
What are:
1. Changes in temperature
2. Observable Chemical/Physical Changes
3. Changes in motion/Changes in shape
400
Explain how Work (Force x Distance) is related to GPE (Mass x Acceleration due to gravity x h)
--> Unit analysis!
Work = Gravitational Potential Energy
Force (F) --> Force of gravity (Fg) --> Mass (m) x Acceleration Due to Gravity (g)
Distance (d) --> Height (h)
Work = F x d is equivalent to GPE = mgh. The work put into an object is equal to the GPE gained by the object.
400
What is Negative work?
Give an example!
Think about a baseball!
Negative Work: When an object’s Ek is is removed by the work put into a system.
Sometimes, doing work on an object reduces its Ek
The force doing the work is in the opposite direction to the motion of the object
400
Which of the laws of thermodynamics are directly related to efficiency?
Both laws of thermodynamics are related directly to efficiency.
1. Energy can be transferred from one object/form to another. --> Energy output vs input
2. Energy conversions can never be 100% efficient.
--> You can never have/calculate more than 100 % efficiency.
400
Which olympic athlete has the most olympic medals?
How many medals does he have?
Michael Phelps · 28 Olympic medals
23 Gold · 3 Silver · 2 Bronze
500
State both Laws of Thermodynamics in full
1. Energy cannot be created or destroyed, but it can be transformed from one form to another, and transferred from one object to another.
2. The conversion of energy can never be 100% efficient, some energy will always be lost in the form of heat.
500
GPE is highest at point B.
The GPE at points A & C is 0 J, GPE only exists when gravity has the ability to do work on an object!
500
The GPE of a roller coaster is 1250 kJ, the kinetic energy produced on the roller coaster was 750000 J. What is the Total Mechanical Energy produced in this roller coaster system? (Report your answer in Joules)
1. 1250 kJ x 1000 J = 1250000 J (GPE)
TME = Eg + Ek
TME = 1250000 J + 750000 J = 2000000 J
TME of the rollercoaster = 2.000 x 106 J
500
Why does the plug-in for our phone charger get hot while charging our phone?
Because the transfer of electrical energy from the outlet into the power cord is not 100% efficient. Some of the energy is lost in the form of heat which causes our plug-in to heat up!
500
What year did the last residential school in Canada close?
The Gordon Residential School in Punnichy, Saskatchewan was the last fully funded residential school in Canada. It closed in 1996 marking the end of this Era in terms of federally-backed cultural assimilation.