Energy forms
The energy stored in chemicals. This is a form of potential or stored energy. This energy is released when chemicals react.
What is Chemical energy
A microwave operates on a 120 V circuit and draws 11 A of current.
Calculate the power used by the microwave.
P= I x V
P=120×11
P = 1320W
What does AC stand for?
What is "Alternating Current"?
A machine transfers 9,600,000 J of energy while operating at 3200 W.
Calculate the operating time in seconds.
t=E/P
t=9 600 000/3200
t=3000s
What is the advantage to new appliances
new vs. old
What are More demand → more power plants needed
The energy of charged particles. Electrons are negatively charged. Electrical energy is transferred when electrons travel from place to place.
What is electrical energy
A space heater uses 1500 W of power on a 125 V outlet.
Determine the current flowing through the heater.
I=P/V
I-1500/125
I=12A
The part that rotates within the magnetic field.
What is the "armature"?
A motor uses 5,400,000 J of energy over 30 minutes.
Determine the power output.
30 x 60=1800s
P=E/t
P= 5 400 000/1800
P=3000W
Why is friction bad in terms of energy?
What is energy loss
The energy possessed by an object because of its motion or its potential to move. A thrown baseball has mechanical energy because of its movement and its potential to fall.
What is Mechanical energy
A phone charger draws 0.8 A of current and uses 9.6 W of power.
Find the voltage supplied to the charger.
V=P/I
V=9.06/0.8
V=12V
Increasing the current within an electromagnet will do this.
What is "increase the strength of the magnet"?
A 75 W television runs for 6.5 hours.
Calculate the energy used in joules.
6.5×3600=23400 s
E=75×23 400
E= 1 755 000J
How can we increase efficiency in heating/cooling Devices
What is insulation
The total kinetic energy of all the particles in a substance. The faster a particle moves, the more kinetic energy it has. Compare two cups holding equal amounts of water: the one containing more thermal energy will feel warmer.
What is Thermal energy
An electric drill connected to a 24 V battery uses 192 W of power.
Calculate the current required.
I=P/V
I=192/24
I=8A
This type of generator/motor has an commutator (single split ring)?
What is "DC"?
A microwave uses 1200 W of power for 3 minutes and 20 seconds.
Determine the energy transferred.
(3 x 60) + 20 =200s
E=P x t
E=1200 x 200
E=240 000J
Efficiency improvements depend on
What is the devices purpose
battery-operated clock
What is chemical transformed into sound, electrical, and mechanical
A gaming computer draws 5.5 A from a 240 V power source.
Determine the power consumption.
P=IxV
P=5.5 x 240
P=1320W
This part interacts with the permanent magnets of a motor.
What is the "electromagnet" or armature?
A sound system rated at 350 W is used during a concert for 5 hours.
Calculate the total energy transferred.
5 x 3600=18 000s
E = P x t
E= 350 x18 000
E=6 300 000J
Devices with movement cannot be
What is fully efficient