Upgrade to remove ads
Motion, Acceleration and Velocity
Terms in this set (34)
What is motion?
Motion is a change in position.
What is a reference frame?
A group of objects that are not moving relative to each other.
What is a reference point?
A point chosen on the reference frame. The position of an object is the distance and the direction of the object from the reference point.
What is an objects motion?
An object doesn't have an absolute motion, the motion is relative or dependent on the chosen reference frame.
What is displacement?
It is the distance and direction of an objects final position from it's initial position. Displacement includes both size and a direction.
What is the size of displacement?
The distance between the initial and final position.
What is a vector?
A quantity that is specified by both a size and direction.
How do distance and displacement differ?
Displacement includes both size and direction, but distance is only how far you have gone.
What is speed?
Speed is the distance an object travels per unit of time. The unit of speed is m/s or meters per second. Speed of object changes as it moves from one place to another.
What is instantaneous speed?
Instantaneous speed is the speed at a single instant of time. ex: car speedometer.
What is average speed?
The total distance traveled divided by the total time traveled. Average speed= total distance/total time
v = d/t can be written in m/s or k/h (meters/second)
What is velocity?
Velocity is the speed of an object and it's direction of motion. Velocity is a vector because it has a size and direction. The size of an object is the object's speed.
Can objects have different velocities?
Yes if they are traveling at different speeds or different different directions
How are velocity and speed different?
Speed is just how fast an object is traveling while velocity is how fast it's object is traveling and it's direction.
How do you graph motion?
Time is always the horizontal axis and distance is always the vertical axis. If your speed is constant you will have a straight line. If object is moving at a constant speed, the distance over equal time intervals is the same.
What is the slope of a line on a graph?
The steepness of the line is the slope of the line. The slope of the line of the graph equals the speed.
What is a horizontal line on a distance/time graph?
It is zero slope and shows the object at rest.
What is acceleration?
Acceleration is the change in velocity divided by the time for the change to occur. A change in velocity can be either a change in speed or direction. Acceleration occurs when the speed of an object or a direction of an object changes.
What happens any time an object changes direction even if it's speed is constant?
The object is accelerating. (horse on carousel)
How do you calculate average acceleration?
calculated in m/s2
final velocity (m/s2) - initial velocity (m/s2)/ final time (s)- initial time (s) a - vf - vi/ tf-ti
What is a speed time graph?
vertical axis is speed, horizontal axis is time. The slope is the objects acceleration. When a slope is upward it is showing positive acceleration and when the slope is downward it is showing negative acceleration.
What is a force?
A force is a push or pull that one object exerts on another. It is a vector that has a size or direction. The size of a force is also called strength of the force. It is measure in newtons. The force can cause a motion of an object to change.
What is a balanced force?
Forces on an object that are equal in size and opposite in a direction. Object doesn't move. Net force is zero.
What is a net force?
A net force is when two or more forces act on an object at the same time.
What is and unbalanced force?
When forces combine to produce a net force that is not zero. When forces are unbalanced from opposite directions, the object moves in the direction of the larger force. The net force will be the difference between the two forces. If the two forces are pushing in the same direction, you add the the two forces together to get the net force.
How does force change velocity.
If forces are balanced there is no change. If it is unbalanced, it does change to the direction of the push of the larger net force.
What is friction
Friction is the force that opposes the sliding motion of two surfaces that are in contact. Friction increases or decrease depending on what materials are in contact with each other and how smooth or rough the surfaces are. Friction is the opposite direction of the push/force.
What is a microweld?
In friction, the microwelds happen when bumps and dips in a surface come into contact and push against one another.
Why does friction occur?
Friction is due to the microwelds that form between two surfaces in contact. These microwelds become stronger when the force pushing the surfaces together increases.
What is static friction?
Static friction is the frictional force that prevents two surfaces in contact from sliding past each other. (I can't push a box forward because the static friction is too great)
What is sliding friction?
Sliding friction is the force that acts in the opposite direction to the motion of a surface sliding on another surface. The force due to sliding friction between two surfaces is smaller than the force due to static friction.
What is rolling friction?
When an object rolls over a surface the frictional force due to rolling friction slows the object down. (easier to move a heavy object on wheels)
What is air resistance?
Air resistance opposes the motion of object that move through the air. It causes an object to fall with different accelerations and speeds. It pushes upward on the object. It depends speed, size and shape of an object, not the mass.
What is terminal velocity?
Terminal velocity is the highest velocity a falling object will reach. It depends on the size, shape and mass of a falling object. The upward force of air resistance and the downward force of gravity eventually balance which causes a net force of zero. (terminal velocity)
THIS SET IS OFTEN IN FOLDERS WITH...
7th Grade Physics Equations
The Language of Science - Definitions
YOU MIGHT ALSO LIKE...
Chapter 3: Motion, Acceleration, and Forces
Chapter 3 Motion Acceleration and Forces
Forces and Motion
Motion, Acceleration, and Forces
OTHER SETS BY THIS CREATOR
Midterm for english
OTHER QUIZLET SETS
Physics Chapter 3
Physics Final (Chapters 5, 6, 19, 20)
Chapter 2: Mechanical Equilibrium
Combo with "Physics Ch.5 Sec.6" and 2 ot…