Physics: Speed, Motion, Distance-Time Graphs & Newton’s Laws

What is average speed?

The total distance an object travels divided by the total time traveled for the entire trip[cite: 29, 30].

What two pieces of information are needed to calculate average speed?

Total distance and total time[cite: 27, 29, 30].

What is the formula for calculating average speed?

Average Speed = Total Distance divided by Total Time (S = TD / TT)[cite: 26, 29, 30].

What is instantaneous speed?

The speed of an object at a specific moment in time[cite: 29, 30].

What is constant speed?

Speed that remains the same or does not change over time[cite: 29].

What is speed?

Distance traveled in a given amount of time[cite: 32].

What is velocity?

Speed in a given direction (Speed + Direction)[cite: 32].

What is distance?

The amount traveled from Point A to Point B[cite: 32].

What is displacement?

The distance between an object's ending point and starting point[cite: 32].

What is direction?

The path of travel (such as North, South, East, West, or toward an object)[cite: 32].

How do you identify speed vs velocity?

Speed only has a measurement and time unit, while velocity includes speed plus a specific direction[cite: 32, 33].

What happens when speed changes?

It causes acceleration[cite: 34].

What happens when direction changes?

Velocity changes even if speed stays the same[cite: 34].

What are common units for distance?

Meters, centimeters, kilometers, or miles[cite: 31, 35].

What are common units for time?

Seconds, minutes, or hours[cite: 31, 35].

What are common units for speed?

Meters per second, kilometers per hour, or miles per hour[cite: 30, 31].

How do you find average speed from a Distance vs Time graph?

Identify total distance and total time from the graph axes, then divide total distance by total time[cite: 35].

What does a straight diagonal line going up on a distance-time graph show?

Constant speed moving away[cite: 35, 37].

What does a flat horizontal line on a distance-time graph show?

An object at rest (no movement)[cite: 37].

What does a curved line on a distance-time graph show?

Acceleration (changing speed)[cite: 37].

Who is credited with developing the 3 laws of motion?

Isaac Newton[cite: 39].

What is Newton's 1st Law of Motion?

An object at rest stays at rest, and an object in motion stays in motion unless acted upon by an unbalanced force[cite: 39, 42].

What is another name for Newton's 1st Law?

The Law of Inertia[cite: 39, 42].

What is inertia?

An object's tendency to resist a change in its motion[cite: 39, 42].

How does mass affect inertia?

The more mass an object has, the more inertia it has[cite: 42].

What is a balanced force?

Equal forces acting on an object that cause no change in its motion[cite: 39, 42].

What is an unbalanced force?

Unequal forces that cause an object to start moving, speed up, slow down, or change direction[cite: 39, 42].

What are examples of balanced forces?

A cell phone resting on a counter, a picture hanging on a wall, or a train moving in a straight line at a constant speed[cite: 39, 40].

What are examples of unbalanced forces?

An airplane accelerating for takeoff, a soccer ball being kicked, or a bowling ball hitting pins[cite: 39, 40].

What is friction?

A force that acts against an object's motion, causing it to slow down[cite: 39, 42].

What is gravity?

A force that affects movement on a slope and causes objects to accelerate downhill[cite: 39, 42].

What is air resistance?

A force that slows down moving objects through the air[cite: 42].

What do the arrow lengths represent in a force diagram?

The magnitude (strength) of the force[cite: 42].

What do the arrow directions show in a force diagram?

The direction of the force acting on the object[cite: 42].

What steps are used to calculate average speed from a word problem?

Read the problem, identify distance and plug into equation, identify time and plug into equation, divide distance by time, and write the correct unit[cite: 30].

What tool helps remember the speed formula?

A triangle with Distance on top, and Speed and Time on the bottom (D over S and T)[cite: 26].

What does a downward sloping line on a distance-time graph represent?

Constant speed returning home[cite: 37].

What kind of force is a game of tug-of-war when nobody is winning?

A balanced force[cite: 39, 40].

What kind of force is a football player tackling a quarterback?

An unbalanced force[cite: 39, 40].

What is a visual representation of forces acting on an object called?

A force diagram[cite: 42].