What is Motion?
Reference point or Frame of Reference
A place or object used for comparison to determine if an object is in motion
scalar quantity
A quantity in physics, such as mass, volume, and time, that can be completely specified by its magnitude, and has no direction.
Newton's First Law
An object at rest stays at rest and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force.
Acceleration happens when
An object speeds up, slows down or changes direction
Formula for Speed
Distance divided by time (d/t)
How is velocity different from speed?
Speed is a description of how fast an object moves; velocity is how fast and in what direction it moves. Speed is a scalar quantity and velocity is vector quantity.
Jamal lives 2 Km from his school. It takes 30 minutes to walk to school. What is Jamal's average speed during his walk in km/hr
Speed=Distance / Time; 2 km /0.5 hrs = 4 kms / hr
motion
a change in position of an object.. Ex. something in motion moves from one place or position to another
vector quantity
a quantity that has both magnitude and direction
gravitational force
an attractive force that acts between any two objects that have mass
acceleration
any change in velocity
balanced forces
forces acting on an object that combine and form a net force of zero
force
push or pull; change the way something is moving
friction
the force that acts directly against the direction of motion. Ex. friction can slow things down or make them stop.
gravity
the force that pulls objects down to Earth. This force keeps you on the ground or on a chair. Force of attraction between the earth and any object on earth.
position
the location of an object in relation to a nearby object or place
speed
the measure of an object's change in position during a certain amount of time. Speed is how many minutes or hours it takes to get from one place to another.
velocity
the speed of an object in a particular direction.
unbalanced force
two or more forces that are not equal and opposite of one another; can cause change in motion
Examples of friction
walking, pushing furniture on a carpet, ball rolling on gravel, rubbing hands together
