Magnets
What is a magnet?
A piece of iron that has a N pole and an S pole
What are the parts of an electromagnet?
Wire, battery, nail
What is energy?
The ability to do work or change your environment
What is momentum?
The quantity of mass times velocity
What are the units of energy?
Joules
What is the iron rule?
Opposite poles attract, like poles repel
What role does the wire play in the electromagnet?
It forces the nail's domains to align and turns it into a magnet
What are the two types of energy?
KE,and PE. Kinetic and potential energy
What has more momentum a car or a bike traveling at the same speed? Why?
The car because it has more mass.
What are the units of electric current?
Ampere or Amps.
What types of materials are attracted to magnets?
Iron
How can an electromagnet be made stronger?
Increase the wraps of wire, increase the current, or reduce the resistance of the circuit.
What is the equation for potential energy?
Energy due to position
What is the momentum of a car (mass=1200 kg)
traveling at 20 m/s
P= 24,000 Ns
What electrical quantity is measured in Ohms?
Resistance
What types of materials are not attracted to magnets?
Plactics, all metals but iron, paper, cardboard, glass,
What advantages does an electromagnet have over a regular magnet?
Turn on/off, stronger, can switch polarity
What is the equation for kinetic energy?
KE= 1/2mv2
What is the total momentum of a system in which one car is traveling 10 m/s to the right (mass=1200) and a second car is traveling 5 m/s to the left (mass=1200)
Ans. 12,000 - 6,000 =6,000
How many centimeters are in a meter?
100
What makes a piece of iron a magnet
The domains must be aligned
Where are electromagnets used? list at least commercial uses.
MRI, Junkyard crane, doors in schools, motors.
What is the law of conservation of energy?
The total energy of a closed system must remain the same.
What speed would a second cart(mass 2 kg) have if it were struck with a cart (mass 4 kg) traveling at 10 m/s. The stationary cart moves and the traveling cart stops as a result of this collision.
Pi=Pf
(4)(10)=(2)(X)
X=40/2=20 m/s
How many grams are in a kilogram?
1,000