Acceleration

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Category: Education
     
 

Presentation Description

The nsecond presentation on motion for mr. Warner's Physical Science class

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Presentation Transcript

Acceleration : 

Acceleration Change in velocity Can be change in speed or direction Acceleration = ∆V/ ∆T ∆V a t

Acceleration problem : 

Acceleration problem A roller coaster’s velocity at the top of a hill is 10m/s. Two seconds later it reaches the bottom of the hill with a velocity of 26m/s. What is the acceleration of the roller coaster?

Answer : 

Answer Acceleration = ∆V/ ∆T a = 26m/s – 10m/s 2 s a = 16m/s 2s a = 8m/s/s or 8m/s2

More acceleration problems : 

More acceleration problems 1. A car accelerates at a rate of 20mi/hr/s. How long does it take to reach a speed of 80 mi/hr? 2. A car travels at 60 miles per hour around a curve. Is the car accelerating? 3. A car travels in a straight line at 60mi/hr. Is the car accelerating?

Answers: : 

Answers: 1. ∆V 80mi/hr a t 20mi/hr/s t 4sec = t 2. yes! Because it’s changing direction! 3. no! It’s not changing speed or direction!

Deceleration : 

Deceleration Negative acceleration Example: A car slows from 60mi/hr to 20mi/hr in 4 seconds. What is its acceleration?

Answer: : 

Answer: Acceleration = ∆V/ ∆T Acceleration = Vf – Vi t a = 20mi/hr – 60mi/hr 4 s a = -40mi/hr 4s a = -10mi/hr/s

Review: Distance-time graph of acceleration : 

Review: Distance-time graph of acceleration

Distance-time graph of deceleration : 

Distance-time graph of deceleration

Review:Speed-time graph of acceleration : 

Review:Speed-time graph of acceleration

Review: Speed-time graph of deceleration : 

Review: Speed-time graph of deceleration

Review: Distance-time graph of constant speed : 

Review: Distance-time graph of constant speed