Newton's Laws
What is Newton's first law of motion?
An object at rest remains at rest; an object in motion remains in motion unless acted upon by an unbalanced force.
What does it mean when forces are balanced? Provide an example.
When forces are balanced, objects in motion will stay in motion and objects at rest will stay at rest. An example of this is a book resting on a table.
Which direction does a compass always points?
North
Mass times velocity
Mass x velocity
What are the three major components of elements?
Protons, neutrons, and electrons.
What is Newton's second law of motion?
Force equals mass x acceleration
F = ma
What does it mean when forces are unbalanced? Provide an example.
When forces are unbalanced, acceleration is happening. This means an object is either moving faster or moving slower. An example of unbalanced forces is kicking a soccer ball (you exert force that accelerates the soccer ball).
What is an example of an electromagnet used in health care settings?
MRI
What is the momentum of a 2 kilogram object moving 3 meters per second North?
2kg x 3m/s = 6 kgm/s
Which particle always has a positive charge?
Proton
What is Newton's third law of motion?
For every action there is an equal and opposite reaction.
What's the difference between mass and weight?
Mass is the amount of matter in an object. Weight is a measure of the amount of force exerted on an object by gravity. Mass is measured in kilograms while weight is measured in pounds. Mass stays the same on every planet and celestial body, while weight changes based on the gravity of the planet.
What are the two poles of a magnet and which poles are attracted and repelled?
North and South poles.
Opposite poles attract each other. (North and South)
Same poles repel each other. (North and North or South and South).
Which unit do we use for force?
Newton
Which particle always has a negative charge?
Neutron
What is the sum of all forces acting on an object called?
Net force
What are the four main types of friction? Name an example of each.
Static friction keeps objects in place. Static friction is what makes it harder to push a heavy object. Sliding friction is when two surfaces rub against each other. Sliding friction is rubbing an eraser on a paper. Rolling friction is caused when an object rolls. An example is rolling a soccer ball on grass. Fluid friction is friction caused by fluids. An example is air resistance or running through water.
What is produced by an electric current?
a magnetic field
Which object will exert the largest friction force: an ice cube, milk, cement, or mud.
cement, it has the roughest surface.
What does the atomic number tell us?
The number of protons in an element. The number of protons determines the element name.
When you throw an object into the air, which force pulls the object back to Earth?
Gravity
What's the difference between speed and velocity?
Velocity indicates the direction. For example, speed would be 60 miles per hour, while velocity would be 60 miles per hour North.
What do you call a current carrying wire that has many loops? Does this create a magnetic field?
Solenoid
Yes, all electric currents create a magnetic field.
What is the difference between insulators and conductors? Give an example of each.
Conductors allow electrons to flow easily and can transfer current. An example is copper. Insulators have tightly bound electrons so they don't transfer current well. An example is plastic.
What will happen if an electron leaves an atom? What happens if an extra electron joins an atom?
When an electron leaves, the atom will have a positive charge. When an extra electron joins, the atom will have a negative charge.