Work/PE/KE
Using the work formula, what is the formula for distance
What is d=W/F
Draw a displacement time graph of uniform motion.
What is (see drawing Ms Greene does for you!)
What is the formula for Mechanical Energy?
What is Em=Ek+Ep.
What is the SECOND law of thermodynamics?
What is thermal energy naturally transfers from high thermal energy to low thermal energy (moves from hot to cold)
Is there such thing (in the real world) as a 100% efficient machine?
No! Only theoretical.
What is work/PE/KE/ME measured in? This is the same as energy.
What is Joules
What is (see graph Ms Greene draws on the board for you!)
In a fossil fuel power plant, what is the initial and final energy type? (Be specific!)
What is chemical potential energy and electrical energy.
What is the first law of thermodynamics?
Thermal Energy cannot be created nor destroyed. Only transformed.
Calculate the % efficiency of a car where 200J of mechanical energy input, with 100J of mechanical energy output.
What is 50%?
What is v = sq. root (2Ek/m)
A car travels 100km [S] to Airdrie, then drives 200km [N] to Edmonton. What is the distance the car travelled?
What is 300km.
30J of work is used to stretch a bungee cord, how much potential energy is in the bungee cord?
What is 30J of EP
Your home refrigerator is and example of what kind of heat system? What makes this possible?
What is the energy input of an incandescent light-bulb with 10% efficiency and 2J of light energy output.
What is 20J of electrical energy input.
2 Parts!
Calculate Force: A ball with 30J of work travels 2m.
What is the kinetic energy?
What is 15J; 30J
A car traveled 100km [S] to Airdrie in 1hr. Then travels 200km [N] to Edmonton in 2 hrs. What is the average speed of the car?
What is 100km/hr (~28m/s)
What is the mechanical energy of a stationary, 100kg roller coaster car which has 4000J of potential energy?
What is 4000J?
Car/train/computer/etc. Thermal --> Mechanical
What is the percent efficiency of a perfect machine?
100%
What is the formula for height using the potential energy formula?
h = Ep/(g x m)
A car traveled 100km [S] to Airdrie in 1hr. Then travels 200km [N] to Edmonton in 2 hrs. What is the average velocity of the car?
What is 33.3km/hr (~0.0926m/s OR 9.26x10-2m/s)
A child tightrope walker with a mass of 24kg has 300J of potential energy, he falls and just before hitting the net what is his speed?
Why is the first law of thermodynamics just like the law of conservation of energy?
Energy (heat or any energy) cannot be created nor destroy, only transformed.
An electric motor has an efficiency of 90% has an energy input of 20J, what is the energy output?
What is 18J.