 # PHYSICS 11 TODAY: Speed and Velocity Review Problems/Worksheets.

## Presentation on theme: "PHYSICS 11 TODAY: Speed and Velocity Review Problems/Worksheets."— Presentation transcript:

PHYSICS 11 TODAY: Speed and Velocity Review Problems/Worksheets

The Study of Motion

As an object moves from one position to another, the length of the straight line drawn from its initial to the final position is called:

The shortest distance between the origin and where the person is located Vector quantity - has magnitude and direction

As an object moves from one position to another, the length of the straight line drawn from its initial to the final position is called:

Δ = a change in… = delta

Δd = a change between final and initial position

A person is 2.0 m to the left of a viewpoint sign enjoying the view. She moves 4.5 m to the right of the sign to get a better view. What is the person’s displacement?

Practice Problems 2.1.1 Page: 39 – 40

503 m a) What is the total distance the golf ball travelled while the golfer was playing the seventh hole?

290 m, right b) What is the Resultant Displacement of the Ball?

equals to the object’s distance travelled over the time interval DIRECTION MAGNITUDE It has NO DIRECTION, only MAGNITUDE

equals to the object’s total distance travelled over the time interval DIRECTION MAGNITUDE It has NO DIRECTION, only MAGNITUDE total

equals to the object’s total distance travelled over the time interval DIRECTION MAGNITUDE It has NO DIRECTION, only MAGNITUDE

equals to the object’s speed at the moment you are measuring the speed Give me an example of when we are interested in measuring instantaneous speed

equals to the object’s speed at the moment you are measuring the speed

What is a car’s average speed if the car makes a 100 km long trip from city A to city B if the first half of the trip is driven at 50 km/h and the second half is driven at 100 km/h?

The average speed would be 75 km/h if the car spent equal time at 50 km/h and 100 km/h.

What is the difference between:

Distance travelled over time TOTAL Distance travelled over time Speed of an object at a particular instant

Constant speed If the speed is not changed over an extended period of time

The total displacement of an object over the time interval during which this displacement occurred is called:

SI Units: meters per second (m/s)

DIRECTIONMAGNITUDE It has DIRECTION and MAGNITUDE

A book is moved once around the edge of a tabletop with dimensions 1.75 m 2.25 m.

0.5 m/s, right

If you know the object’s position at specific times, you can determine its VELOCITY Position vs. Time Graph If the VELOCITY is constant, the graph of position vs. time is a straight line. The slope indicates the VELOCITY

Doing this problem GRAPHICALLY

0.5 m/s, right Slope = velocity

The positions of three runners were recorded at specific times. Here are their results: Position vs. Time Graph RUNNER 1 POSITION (km)TIME (min) 00 510 21 1529 2040 RUNNER 2 POSITION (km)TIME (min) 00 -58 -1015 -1525 -2030 RUNNER 3 POSITION (km)TIME (min) 00 512 1024 1533 2047 Describe the motion represented by each graph

Positions of runners over time Time (min) Position (km)

The positions of three runners were recorded at specific times. Here are their results: Velocity = ? RUNNER 1 POSITION (km)TIME (min) 00 510 21 1529 2040

Positions of runners over time Time (min) Position (km)

The positions of three runners were recorded at specific times. Here are their results: Velocity = slope RUNNER 1 POSITION (km)TIME (min) 00 510 21 1529 2040

The positions of three runners were recorded at specific times. Here are their results: RUNNER 2 POSITION (km)TIME (min) 00 -58 -1015 -1525 -2030 Velocity = ?

Positions of runners over time Time (min) Position (km)

The positions of three runners were recorded at specific times. Here are their results: RUNNER 2 POSITION (km)TIME (min) 00 -58 -1015 -1525 -2030 Velocity = ?

The positions of three runners were recorded at specific times. Here are their results: RUNNER 3 POSITION (km)TIME (min) 00 512 1024 1533 2047 Velocity = ?

Positions of runners over time Time (min) Position (km)

The positions of three runners were recorded at specific times. Here are their results: RUNNER 3 POSITION (km)TIME (min) 00 512 1024 1533 2047 Velocity = ?

HOMEWORK Textbook : pg. 44 – 47 #1, #3, #5, #7

Is a velocity of an object at some instant (moment) at a specific point in the object’s path

Each moment a subject moves through larger and larger displacements If the VELOCITY is NOT constant, the graph of position vs. time is a curve. How can we find out the VELOCITY at some exact time (3 sec)?

Construct a STRAIGHT LINE which is TANGENT to the curve at that time

The slope of that STRAIGHT LINE = INSTANTANEOUS VELOCITY