What is Motion???

What is Motion???

Motion—the movement of an object in relation to something considered stationary(a frame of reference)!!!

Frame of Reference

Motion Terms:

• Distance vs. Displacement– Distance—How far you move.– Displacement—How far you are from where you

started!!

50 m

A Student walks from A to B to C to D and back to A. What distance did the student travel?

A.0 metersB.6 metersC.10 metersD.12 meters

A Student walks from A to B to C to D and back to A. What is the student’s displacement?

A.0 metersB.6 metersC.10 metersD.12 meters

Distance Vs. Displacement

• Speed vs. Velocity– Speed—How fast you move!!– Velocity—Speed in a particular direction!!

Other Motion Terms:

Instantaneous vs. Average SpeedInstantaneous Speed• The speed at any instant in

time.

Average Speed• Total distance divided by

total time.

The Velocity Equation:

• Where: d is distance(displacement)----given in m or km t is time----given in s or hr v is velocity-----given in m/s or km/hr

Same equation used for speed!!!

Solving Word Problems:

1. Write down what you are given(the important stuff like #’s, etc.).

2. Write down what you are looking for!3. Find an equation that fits what you have.4. Solve the equation for what you are looking

for!5. Plug and Chug!!

Using the Velocity Equation:

Ex.) A person walks 50 m in 12 s. At what velocity did the person travel?

Given:d = 50 mt = 12 s v = ?

Ex.) A car is moving down the road at 25 m/s. How far will it travel in 18 s?

Given:v = 25 m/st = 18 sd = ?

Ex.) A whale is swimming across the ocean at 14 m/s. How long will it take the whale to swim 1000 m?

Given:v = 14 m/sd = 1000 m t = ?

A car moves a distance of 2400 m in 55 s. How fast is the car moving?

A. 32 m/sB. 44 m/sC. 60 m/sD. 72 m/s

A little girl walks 75 m to his grandmother’s house at 3 m/s. How long will it take her to walk that distance?

A.225 sB.78 sC.35 sD.25 s

Distance Vs. Time Graphs

What can be determined by the slope of a distance time graph?

When does the slope of a distance

time graph = velocity?

Yo Adrian, You know, You know it’s Always !!!

Straight Line, therefore constant Velocity!!

Line not straight, therefore velocity not constant. If velocity is not constant, object must be accelerating!!

In which of the following graphs is the runner running the fastest?

Which of the following graphs indicates that one of runners started 10 yards ahead of the other?

In which of the following graphs are both runners moving at the same speed?

Which sentence best describes the runner whose distance-time graph is shown?

A. The runner ran forward for 2 seconds, and then he ran backward for 2 more seconds. B. The runner ran forward for 2 seconds, and then he stood still for 2 more seconds. C. The runner ran forward for 2 seconds, and then he ran forward at a slower pace for 2 more seconds. D. The runner ran forward for 2 seconds, and then he turned right and continued forward at the same speed for 2 more seconds.