 # WHAT IS SPEED? Speed is how fast an object is moving relative to another object. A frame of reference is necessary to calculate speed. Speed depends on.

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WHAT IS SPEED? Speed is how fast an object is moving relative to another object. A frame of reference is necessary to calculate speed. Speed depends on your point of view, where you are looking from.

WHAT IS SPEED? Speed is how fast an object is moving relative to another object. Speed is defined as a ratio (fraction) of how far an object moves to how long it takes to get there.

WHAT IS THE FORMULA FOR SPEED?
The formula for speed is: SPEED = DISTANCE ÷ TIME OR s = d/t

WHAT IS THE FORMULA FOR SPEED?
The formula for speed is: SPEED = DISTANCE ÷ TIME OR s = d/t The formula can also be used to calculate time: t = d/s or to calculate distance: d = s x t

HOW DO WE MEASURE SPEED? The SI unit (or scientific unit) for speed is meters per second, abbreviated m/s. Meters per second tells us how many meters an object travels in one second.

WHAT IS AVERAGE SPEED? Average speed is calculated for the entire trip. The formula is: v = total distance or d total time t

WHAT IS INSTANTANEOUS SPEED?
Instantaneous speed is the speed of an object at a particular instant or given moment in time. This is what is shown on the speedometer of a car.

HOW DO YOU GRAPH SPEED? Speed can be graphed on a distance-time graph.
The slope of the line is speed.

HOW DO YOU GRAPH SPEED? Speed can be graphed on a distance-time graph.
The slope of the line is speed. Steep slope shows high speed.

HOW DO YOU GRAPH SPEED? Speed can be graphed on a distance-time graph.
The slope of the line is speed. Steep slope shows high speed. Zero slope or straight, horizontal line shows zero speed.

HOW DO YOU GRAPH SPEED? Speed can be graphed on a distance-time graph.
The slope of the line is speed. Steep slope shows high speed. Zero slope or straight, horizontal line shows zero speed. Straight line shows constant speed, speed is not changing.

HOW DO YOU GRAPH SPEED? Speed can be graphed on a distance-time graph.
The slope of the line is speed. Steep slope shows high speed. Zero slope or straight, horizontal line shows zero speed. Straight line shows constant speed, not changing. Curved line shows changing speed.

Velocity is a vector (arrow) that describes both speed and direction.
WHAT IS VELOCITY? Velocity is a vector (arrow) that describes both speed and direction.

WHAT IS VELOCITY? Velocity is a vector that describes both speed and direction. A change in velocity can be result of a change in speed, a change in direction, or both.

WHAT IS VELOCITY? Velocity is a vector that describes both speed and direction. A change in velocity can be result of a change in speed, a change in direction, or both. If an object only changes direction, but not its speed, it has changed its velocity. If speed changes, size of arrow changes. If direction changes, direction of arrow changes

HOW DO YOU COMBINE VELOCITIES?
Because velocity is shown by vectors, you can combine these vectors the same way we did to find displacement.

HOW DO YOU COMBINE VELOCITIES?
Because velocity is shown by vectors, you can combine these vectors the same way we did to find displacement. When you combine vectors, you get displacement or net motion of an object.

WHAT IS ACCELERATION? Acceleration is a change in velocity – a change in speed, or a change in direction, or both.

WHAT IS ACCELERATION? Acceleration is a change in velocity – a change in speed, or a change in direction, or both. Acceleration can be speeding up, slowing down or turning.

WHAT IS ACCELERATION? Acceleration is a change in velocity – a change in speed, or a change in direction, or both. Acceleration can be speeding up, slowing down or turning. Change in direction is also acceleration.

WHAT IS ACCELERATION? Acceleration is a change in velocity – a change in speed, or a change in direction, or both. Acceleration can be speeding up, slowing down or turning. Change in direction is also acceleration. Acceleration is a vector.

WHAT IS ACCELERATION? Acceleration is a change in velocity – a change in speed, or a change in direction, or both. Acceleration can be speeding up, slowing down or turning. Change in direction is also acceleration. Acceleration is a vector. Acceleration can be positive or negative.

WHAT IS ACCELERATION? Acceleration is a change in velocity – a change in speed, or a change in direction, or both. Acceleration can be speeding up, slowing down or turning. Change in direction is also acceleration. Acceleration is a vector. Acceleration can be positive or negative. Positive is speeding up. Negative is slowing down (deceleration).

WHAT IS ACCELERATION? Acceleration is a change in velocity – a change in speed, or a change in direction, or both. Acceleration can be speeding up, slowing down or turning. Change in direction is also acceleration. Acceleration is a vector. Acceleration can be positive or negative. Positive is speeding up. Negative is slowing down (deceleration). Unit of measurement is m/s2 (or meters per second per second).

WHAT IS CONSTANT ACCELERATION?
Constant acceleration is a steady change in velocity

WHAT IS CONSTANT ACCELERATION?
Constant acceleration is a steady change in velocity An object accelerates at the same rate during a certain period of time.

WHAT IS CONSTANT ACCELERATION?
Constant acceleration is a steady change in velocity An object accelerates at the same rate during a certain period of time. During constant acceleration, an object is speeding up or slowing down or turning at the same rate. The force of gravity is constant acceleration of 9.8 m/s2

HOW DO YOU CALCULATE ACCELERATION?
Formula for acceleration is: Acceleration = Change in Velocity divided by Time, or:

HOW DO YOU CALCULATE ACCELERATION?
Formula for acceleration is: Acceleration = Change in Velocity divided by Time, or: To calculate acceleration, subtract beginning speed from final speed, then divide by time. If change in acceleration is a change in direction, subtract vectors.

Measuring Acceleration
Section 11.3

Measuring Acceleration
Section 11.3

Measuring Acceleration
Section 11.3

Measuring Acceleration
Section 11.3

HOW DO YOU GRAPH ACCELERATION?
Acceleration can be graphed on a speed-time graph. The slope of the line is acceleration. Steep slope shows high acceleration. Zero slope or straight, horizontal line shows zero acceleration. Straight line shows constant acceleration.

HOW DO YOU GRAPH ACCELERATION?
Acceleration can be graphed on a speed-time graph. The slope of the line is acceleration. Steep slope shows high acceleration. Zero slope or straight, horizontal line shows zero acceleration. Straight line shows constant acceleration. Positive slope shows positive acceleration. Negative slope shows negative acceleration.

Speed-Time Graphs Figures 16 and 17

Speed-Time Graphs Figures 16 and 17

Distance-Time Graph of Accelerated Motion
Figure 18

FREEFALL AND GRAVITY When an object falls, the force of gravity makes it speed up or accelerate. The acceleration caused by gravity is about 9.8 m/s2. Because of friction or air resistance, objects on Earth will reach a terminal velocity, and acceleration will stop. The object will thereafter continue falling at the same speed.

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