What is a non-contact force
#3 A force that can cause creates a push or a pull without touching it.
What is an independent variable
#1 What the scientst is testing, what the scientist is changing
What are three parts to an electromagnet?
#6 Battery, copper wire, nail
What are the parts to a motor?
#9 An electromagnet (battery, copper wire, paperclip) and a permanent magnet
What happens to the strength of the magnetic field or static elecrtical field when the distance between the magnetis DECREASES?
#27 It is stronger bc it is closer.
What is a dependent varibale?
#2 What the scientist measures, the DATA collected.
What is the difference between a parmanent magnet and an electromagnet?
#7 A permanent magnet always has a magnetic field. An electromanget is a temporary magnet.
What are motors used for?
#9 We put them in items to make them move/power them. Cars, remote control toys, fans, household appliances.
Draw two magnets repelling each other
Draw two magnets attracting each other
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In an experiment testing the number of wire turns on a nail and the number of paperclips it picks up. What is the independent variable and what is the dependent variable?
#19 Independent- number of coils (what the scientist is changing)
Dependent- number of paperclips picked up- data collected to measure strength.
How can a student test which electromagnet is stronger?
#15 Which one picks up more paperclips.
How are motors different than generators?
#8 Generators generate electricity. Motors power appliances/make things power on.
What are three examples of non-contact forces that we have learned about?
#3. Magnetism, electricity, and gravity
What is the independet variable? Dependent variable?
1. Place a 20 kg cart at one end of a 30 m hallway
2. Apply a force to the cart
3. Measure how far the cart moves before it stops rolling.
4. Repeat steps 1-3 using different amounts of force each time.
5. Create a graph of the amount of force used and distance achieved by the cart for each test.
Independent: differerent amounts of force- what the scientist is changing
Dependent: distance the car travels- data collected- what is being measured.
What are four ways you can strengthen an electromagnet?
Question 13 on study guide
1) Bigger/more batteries
2) More coils
3) Thicker copper wire
4) Closer distance
5) Bigger nail
Explain how a motor works
#30 A motor works because the magnetic field from an electromagnet and the magnetic field of the permanent magnet are constantly interacting causing the coil to spin/rotate.
Remember the charges
You are able to create static elecrticity by using fricition. Take a wool cloth and rub it against the balloon. The elecrtons will be transferred from the wool to the balloon. The wool then has a positive charge while the balloon has a negative charge. The balloon will be able to attract to someone hair.
A student discovered that motors are built on the concept of electromagnets. Motors are used in many of the items found in home, such as electric toothbrushes, ceiling fans, and vacuum cleaners. Since motors use electromagnets, the student decided to build his own. The student constructed a model of a small motor using an electromagnet. The model will be tested to see if it works when a copper wirse is attached to a battery.
The student looped the copper wire in a circle with the ends straightened out. The paper clips were reshaped and used to hold the wire, and the rubber band was used to hold the paperclips against the battery.
The student discovered that the copper loop began to spin very quickly. He also discovered that when the magnet on the battery was moved farther away the spinning of the copper loop slowed down.
The student revised the procedure to make the copper loop spin faster by adding more loops to the copper wire. The student observed that it did spin faster when more loops were added
Independent= changing the number of coils
Dependent (data)= speed of the copper wire
Why do you need a battery, a nail, and copper wire to make an electromagnet?
Battery- power source, provides electrons
Copper wire- conductor- transfers electrons
Nail- ferromagnetic- need something magnetic for the magnet
Draw a model of a motor?
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