POSITION-TIME GRAPHS & SPEED-TIME GRAPHS YEAR 12 UNIT 1 MODULE 1 LESSON 5

UNIFORM VELOCITY - CONSTANT

Draw a set of axes. Time in seconds along the x- axis. Displacement in metres up the y-axis. Draw up to 10 on both axes.

DRAW THE FOLLOWING: A LINE ON THE GRAPH TO REPRESENT: A) STOOD STILL AT POSITION, 0M

B) STOOD STILL AT 3M

C) WALKING STEADILY AT 1M/S, STARTING AT POSITION 0M

D) WALKING STEADILY AT 4M/S, STARTING AT POSITION 2M

E) ACCELERATING WHILST WALKING FORWARD (DON’T WORRY ABOUT NUMBERS, JUST SHOW ME THE RIGHT SHAPE OF LINE)

F) DECELERATING WHILST WALKING FORWARD

G) STARTING AT 10M AND WALKING AT 2M/S BACK TO THE START POINT (0M)

H) WALKING FORWARDS AT 2M/S FOR 3 SECONDS, AND THEN STANDING STILL FOR 4 SECONDS, BEFORE RUNNING BACK TO THE START POINT (0M) AT 6M/S

ON YOUR PAPER (AS OPPOSE TO WHITEBOARDS), TRY TO DRAW ALL THE SEPARATE LINE ELEMENTS FOR A DISPLACEMENT-TIME GRAPH E.G. STEADY POSITIVE VELOCITY

A few of the possible lines on a displacement – time graph. Can you think of any others?

EACH TYPE OF MOTION ON A DISPLACEMENT-TIME GRAPH SLIDE COMING SOON, TO A WHIEBOARD NEAR YOU! (PROBABLY JUST WANT TO WRITE THEM DOWN FOR NOW) 15/09/06

DISCUSS IN PAIRS, WRITE YOUR ANSWER ON YOUR WHITEBOARDS: WHAT WOULD LOOK DIFFERENT ON A DISPLACEMENT-TIME GRAPH TO A DISTANCE-TIME GRAPH?

NEGATIVE DISPLACEMENT. (I.E. MOVING BACK TOWARDS WHERE YOU STARTED), TECHNICALLY SPEAKING, ON A DISTANCE-TIME GRAPH, YOU CANNOT HAVE A NEGATIVE DISTANCE, AS DISTANCE IS A SCALAR.

TAYA WALKS A STEADY VELOCITY FOR 15 SECONDS, FOR 60M SHE THEN STAYS STATIONARY FOR 20 SECONDS AND THEN WALKS A STEADY VELOCITY FOR 5 MORE SECOND, FOR 10M SHE THEN RETURNS THE 70M HOME OVER 60 SECONDS, BY WALKING AT A STEADY SPEED DRAW THIS DISPLACEMENT-TIME GRAPH HOW CAN YOU FIND TAYA’S VELOCITY AT A GIVEN POINT IN HER JOURNEY FROM THIS GRAPH?

THE GRADIENT OF DISPLACEMENT-TIME GRAPH IS VELOCITY!!!!!!!!!!!!!!!!! BECAUSE: GRADIENT = CHANGE IN Y / CHANGE IN X = CHANGE IN DISPLACEMENT / CHANGE IN TIME = CHANGE IN VELOCITY WHAT WOULD THE GRADIENT OF A DISTANCE-TIME GRAPH BE?

-GO THROUGH MOTION GRAPH QUESTION ON BASELINE TEST

EXAM QUESTIONS

ANSWERS

WALKING DISPLACEMENT-TIME GRAPHS

SPEED-TIME & VELOCITY-TIME GRAPHS

LOOK AT ALL YOUR POSSIBLE LINES FROM DISPLACEMENT-TIME GRAPH. WHAT WOULD THEY LOOK LIKE ON A VELOCITY-TIME GRAPH? CAN YOU ADD ANY MORE LINES?

EACH TYPE OF MOTION ON A VELOCITY-TIME GRAPH SLIDE COMING SOON, TO A WHIEBOARD NEAR YOU! (PROBABLY JUST WANT TO WRITE THEM DOWN FOR NOW) (ALMOST AS MUCH OF AN ANTI-CLIMAX AS THE FIRST TIME I SHOWED THIS SLIDE) 15/09/06

Template copyright Draw a displacement –time graph for bob’s journey. Distance should be along the y-axis, and time on the x-axis Bob is out for a walk. He starts travelling at 0.5m/s for 20 secs He then jogs on for 10 secs at a speed of 5m/s He then stops for 10 seconds to remember what he forgot but can't. He suddenly remembers what it was and walks back at for 20 secs at 3m/s

DRAW THE SPEED-TIME GRAPH FOR BOB’S JOURNEY WHAT DOES THE GRADIENT OF THIS GRAPH TELL US ABOUT A GIVEN PARTO F HIS JOURNEY? HOW CAN WE FIND THE DISTANCE TRAVELLED FROM THIS GRAPH?

GRADIENT OF A VELOCITY-TIME GRAPH IS ACCELERATION AREA UNDERNEATH THE GRAPH IS DISTANCE TRAVELLED

SPEED-TIME GRAPHS IN TERMINATOR 2 (ONE OF THE TERMINATOR FILMS THAT DIDN’T SUCK… I’M LOOKING AT YOU TERMINATOR 3) RECORD THE TIME THAT EACH FO THE EVENTS HAPPEN IN THE CHASE AND FIL LTHEM IN ON THE SHEET. FROM HERE WE CAN PLOT A SPEED-TIME GRAPH

HOMEWORK

EXTRA SLIDES ADD HOMEWORK ADD EXAM QUESTIONS SORT OUT PICTURES OF ALL LINE ELEMENT SLIDES GATHER RESOURCES E.G. TERMINATOR ONES

HOW CAN WE WORK OUT VELOCITY FROM A DISPLACEMENT-TIME GRAPH? VELOCITY IS RATE OF CHANGE OF POSITION. WE NEED TO FIND OUT HOW RAPIDLY THE POSITION IS CHANGING OUR GRAPH LETS US DO THIS EASILY – IT’S SIMPLY THE GRADIENT!!!

WHAT ABOUT DISTANCE-TIME GRAPHS? CAN WE HAVE A NEGATIVE VALUE ON A DISTANCE-TIME GRAPH? NO – DISTANCE IS JUST THE PATH TAKEN, IT HAD NO DIRECTION, HENCE NEGATIVE DISTANCE DOESN’T REALLY MEAN ANYTHING WHAT WOULD THE GRADIENT OF A DISTANCE-TIME GRAPH BE? SPEED, SPEED = DISTANCE/TIME

WRITE 3 QUESTIONS ON A PIECE OF PAPER. ANYTHING FROM THIS LESSON…