# Using the Equations of Motion

## Presentation on theme: "Using the Equations of Motion"— Presentation transcript:

Using the Equations of Motion

Step One: What each term means
Distance, s, is how FAR you are from your starting position.

Step One: What each term means
Distance, s, is how FAR you are from your starting position. START

Step One: What each term means
Distance, s, is how FAR you are from your starting position. START s = 10 m

Step One: What each term means
Distance, s, is how FAR you are from your starting position. No matter HOW you got there… START s = -5 m

Step One: What each term means
Velocity is how FAST you are going

Step One: What each term means
Velocity is how FAST you are going v = 10 m/s

Step One: What each term means
Velocity is how FAST you are going It can be negative v = -15 m/s

Step One: What each term means
Velocity is how FAST you are going It can be negative It is simply distance traveled divided by the time. s t vave =

Step One: What each term means
Acceleration is how quickly the velocity changes.

Step One: What each term means
Acceleration is how quickly the velocity changes. Positive a means you are speeding up

Step One: What each term means
Acceleration is how quickly the velocity changes. Positive a means you are speeding up Negative a means you are slowing down

Step One: What each term means
Acceleration is how quickly the velocity changes. Positive a means you are speeding up Negative a means you are slowing down It is change in velocity divided by the time.

Step One: What each term means
Acceleration is how quickly the velocity changes. Positive a means you are speeding up Negative a means you are slowing down It is change in velocity divided by the time. Δv t a =

Step One: What each term means
Acceleration is how quickly the velocity changes. Positive a means you are speeding up Negative a means you are slowing down It is change in velocity divided by the time. Δv t v - u t a = =

Step One: What each term means
Acceleration means the final velocity is NOT the same as the initial velocity.

Step One: What each term means
Acceleration means the final velocity is NOT the same as the initial velocity. We use initial velocity = u

Step One: What each term means
Acceleration means the final velocity is NOT the same as the initial velocity. We use initial velocity = u We use final velocity = v

Step One: What each term means
Acceleration means the final velocity is NOT the same as the initial velocity. We use initial velocity = u We use final velocity = v If v > u then we are speeding up (a is positive)

Step One: What each term means
Acceleration means the final velocity is NOT the same as the initial velocity. We use initial velocity = u We use final velocity = v If v > u then we are speeding up (a is positive) If v < u then we are slowing down (a is negative)

Equation One: v = u + at A train accelerates from rest at 3 m/s2. How fast is it going after 30 seconds? My Nissan Frontier goes from 0 to 60mph in 9.2 seconds, What is the acceleration? A car traveling at 30 m/s decelerates at 7 m/s2. How long is it before it comes to rest? An ice puck slows due to friction at 1.7 m/s2. I hit the puck at one end of the rink, and when it hits the goal, 12 seconds later, it is going at 19 m/s. At what speed did I hit the puck initially?

Equation Two: s = ut + ½at2
A train accelerates from rest at 3 m/s2. How far has it gone after 30 seconds? From a rolling start at 20 mph, Jewel Alderson can cover the 400 meter Trader Joes parking lot in 11 s, What is the acceleration of her Hyundai? An ice puck on asphalt slows due to friction at 6.7 m/s2. It travels 100 meters in 7 seconds. At what speed did I hit the puck initially?

Equation Three: v2 = u2 + 2as
A train accelerates from rest at 3 m/s2. How fast is it going when it hits the car on the track, 500 meters down the line from the station? Traveling at 60 mph I see an old person walk into the road 300 meters ahead. Feeling in a good mood, I decide to break, and the car slows at a rate of 6.5 m/s2. What is the fate of the pensioner? After joining the freeway I can accelerate from 40 mph to 90 mph in 11 seconds. How far do I travel along the freeway before I get to 90?

Motion Under Gravity I drop an egg from the bridge in Balboa Park and it hits a car windscreen 5 seconds later. How high is the bridge? I throw a pool ball straight up into the air and it hits the ground 3.5 seconds later. How fast did I throw the ball? I launch a tennis ball at 45o at a velocity of 40 m/s. How far away does it hit the ground? A golfer hits a ball and 3 seconds later gets a hole in one If the hole was 250 meters away, what was the highest point in the ball’s trajectory?