Competency 31: Forces and Motion

Question 1

Push

Answer 1

force used to move something away from the force, such as pushing a shopping cart.

Question 2

Pull

Answer 2

Force used to move something towards the force, such as pulling a wagon.

Question 3

Friction

Answer 3

Force acting in the opposite direction of the motion of an object. A car being stopped by its tires against the road.

Question 4

Gravity

Answer 4

Force that pulls objects towards the Earth. If you drop a pencil, gravity is the reason it falls down.

Question 5

Electric Force

Answer 5

Force of positive or negative attraction between atomic particles such as electrons, protons, and neutrons. Static electricity.

Question 6

Magnetic Force

Answer 6

Force that pulls objects toward or away from a magnetic field.

Question 7

Inertia

Answer 7

Tendency of an object to resist changes in its motion. Its hard to move heavy fridge because of this.

Question 8

Scientific Method

Answer 8

1) Questioning
2) Hypothesizing
3) Observation
4) Data Collection
5) Drawing Conclusions

Question 9

Motion

Answer 9

Refer to a continuous change in the position of a body relative to a reference point.

Question 10

3 ways of measuring, graphing, and describing changes in motion

Answer 10

1) Displacement: vector quantity that describes position of a particle in reference to an origin.
2) Velocity: The speed of an object in a particular direction.
3) Acceleration: Vector quantity defined as the rate of change of velocity. Measured in meters/second2.

Question 11

Sir Isaac Newton

Answer 11

1st to give a mathematical definition of force. Came up with 3 laws that define motion.

Question 12

Newtons 1st Law of Motion

Answer 12

States that an object at rest will remain at rest, while an object in motion at constant velocity will remain in motion at constant velocity, unless there is a net force acting on it. The Law of Inertia.

Question 13

Newton’s Second Law of Motion

Answer 13

When the net force acting on an object is not zero, then the object will move in the direction of the force; in this case the acceleration is directly proportional to the net force and inversely proportional to the mass of he object. 
F=net force
m=mass of object
a=acceleration
 a=F/m or F=ma

Question 14

Newton’s 3rd Law of Motion

Answer 14

When one object exerts force on another object, the second object will exert a force on the 1st object that is equal in magnitude but opposite in direction. For every action, there is an equal and opposite reaction. Example of action-reaction forces.