1. “There is more to life than simply increasing its speed.” ― Mahatma Gandhi -Mahatma Gandhi

2. ACCELERATION – CHANGE IN VELOCITY WITH CHANGE IN TIME WHEN YOU ARE RIDING IN A CAR, YOU DON’T NOTICE SLIGHT CHANGES IN VELOCITY OR SPEED. HOWEVER, IF THEY ARE LARGE ENOUGH, YOU NOTICE THEM. IMAGINE A VISIT FROM YOUR CRAZY UNCLE HARRY. HE’S JUST PURCHASED A NEW F TYPE JAGUAR, AND HE WANTS TO TAKE YOU FOR A RIDE.

3. YOU GET IN THE CAR AND FASTEN YOUR SAFETY HARNESS, BECAUSE YOU’VE DRIVEN WITH UNCLE HARRY BEFORE. UNCLE HARRY DRIVES VERY CALMLY OUT OF TOWN. WHEN HE GETS TO THE LAST STOP LIGHT, HE HAS TO STOP FOR A RED LIGHT. WHEN THE LIGHT TURNS GREEN, THERE ARE NO OTHER CARS AROUND, SO THE STOMPS ON THE GAS. THE CAR CAN REACH 60 MPH AND 3.6 SECONDS, AND YOU FEEL LIKE IT DOES. YOU ARE PUSHED BACK INTO YOUR SEAT.

4. UNCLE HARRY SLOWS DOWN TO 50 MPH WHICH IS THE SPEED LIMIT. HE HOLDS THIS SPEED EVEN THROUGH A VERY SHARP CURVE. THE CAR TAKES THE CURVE REALLY WELL – BETTER THAN YOU, AS YOU ARE PUSHED AGAINST THE DOOR ON YOUR SIDE. THE DRIVE CONTINUES OUT INTO THE COUNTRY. WHEN YOU ARE ON A LONG, STRAIGHT STRETCH WITH NO OTHER CARS AND NO HOUSES IN SIGHT, UNCLE HARRY JAMS THE BREAKS. THE CAR SLOWS FROM 50 MPH TO A STOP IN 6 SECONDS

5. NOW, WHICH OF THESE INCIDENTS WERE EXAMPLES OF ACCELERATION?

6. LET’S GO BACK TO OUR DEFINITION OF ACCELERATION. IT IS THE CHANGE IN VELOCITY WITH CHANGE IN TIME. THE UNITS FOR VELOCITY ARE METERS/SECOND, m/sec. THE UNITS FOR ACCELERATION, SINCE ACCELERATION, a, IS GIVEN AS a =  v /  t ARE METERS/SECOND/SECOND OR m/sec/sec, WHICH IS USUALLY WRITTEN AS m/sec 2

7. NOW, VELOCITY IS A VECTOR QUANTITY, SO ACCELERATION IS ALSO A VECTOR QUANTITY. IT WILL INCLUDE A MAGNITUDE (NUMERICAL VALUE AND UNIT) AND A DIRECTIION. SO ACCELERATION CAN OCCUR IN 3 WAYS 1)CHANGE IN VELOCITY 2)CHANGE IN DIRECTION 3)OR BOTH

8. THREE GOOD EXAMPLES OF ACCELERATION OCCURRED IN UNCLE HARRY’S RIDE: 1)SCRATCHING OFF FROM THE STOP LIGHT 2)GOING AROUND THE SHARP CURVE WITHOUT CHANGING SPEED (CHANGED DIRECTION) 3)THE FAST STOP – SOMETIMES CALLED DECELLERATION (NEGATIVE CHANGE IN VELOCITY)