Phys 11: chap 2, Pg 3phy21bio/Presentations/CH1.pdf3 Phys 11: chap 2, Pg 5 Phys 11: chap 2, Pg 6...

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1 Phys 11: chap 2, Pg 2

Transcript of Phys 11: chap 2, Pg 3phy21bio/Presentations/CH1.pdf3 Phys 11: chap 2, Pg 5 Phys 11: chap 2, Pg 6...

Page 1: Phys 11: chap 2, Pg 3phy21bio/Presentations/CH1.pdf3 Phys 11: chap 2, Pg 5 Phys 11: chap 2, Pg 6 average speed = total distance traveled total time speed and velocity measure how position

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Phys 11: chap 2, Pg 2

Page 2: Phys 11: chap 2, Pg 3phy21bio/Presentations/CH1.pdf3 Phys 11: chap 2, Pg 5 Phys 11: chap 2, Pg 6 average speed = total distance traveled total time speed and velocity measure how position

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Phys 11: chap 2, Pg 3

Phys 11: chap 2, Pg 4

Page 3: Phys 11: chap 2, Pg 3phy21bio/Presentations/CH1.pdf3 Phys 11: chap 2, Pg 5 Phys 11: chap 2, Pg 6 average speed = total distance traveled total time speed and velocity measure how position

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Phys 11: chap 2, Pg 5

Phys 11: chap 2, Pg 6

average speed = total distance traveled

total time

speed and velocity measure how position changes with time

t

x

Δ x

Δ t

trajectory

t1

x1

t2

x2

average velocity = displacement total time

x2 – x1 t2 – t1

= Δx Δt

=

formula for a slope!

vav = slope connecting line from t1 to t2

Page 4: Phys 11: chap 2, Pg 3phy21bio/Presentations/CH1.pdf3 Phys 11: chap 2, Pg 5 Phys 11: chap 2, Pg 6 average speed = total distance traveled total time speed and velocity measure how position

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Phys 11: chap 2, Pg 7

1)  more than 40 mi/hr

2)  equal to 40 mi/hr

3)  less than 40 mi/hr

Phys 11: chap 2, Pg 8

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Phys 11: chap 2, Pg 9

The velocity at a specific instant of time

v(t2 ) = slope of line tangent to path at t2

Review: Average velocity between x1 and x2

t

x

Δ x

Δ t t1

x1

t2

x2

vav = Δx Δt

Take two times very close to each other so Δt is very small

t

x Δ x

Δ t

v = limit = Δt→0

Δx Δt

What is the velocity right at point x2 at the instant the time is t2

Inst

anta

neou

s Av

erag

e

dx dt

Phys 11: chap 2, Pg 10

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Phys 11: chap 2, Pg 11 moving along +x but slowing down

x-axis

Phys 11: chap 2, Pg 12

acceleration measures how the velocity changes with time

average acceleration = change in velocity total time

v2 – v1 t2 – t1

= Δv Δt

=

formula for a slope!

t

v

Δ v

Δ t t1

v1

t2

v2

Aver

age

slope → a

t

v

t

Inst

anta

neou

s

slope of tangent → a

a = limit = Δt→0

Δv Δt

dv dt

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Phys 11: chap 2, Pg 13

1.  1 2.  2 3.  3 4.  4

v

t 1

t 2

v

t 3 v

t 4

Phys 11: chap 2, Pg 14

v

t 1

v

t 2

v

t 3 v

t 4

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Phys 11: chap 2, Pg 15

1.  Choice One 2.  Choice Two 3.  Choice Three 4.  Choice Four

v

t 1

t 2

v

t 3 v

t 4

Phys 11: chap 2, Pg 16

v

t 1

v

t 2

v

t 3 v

t 4

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Phys 11: chap 2, Pg 17

1.  Choice One 2.  Choice Two 3.  Choice Three 4.  Choice Four

v

t 1

t 2

v

t 3 v

t 4

Phys 11: chap 2, Pg 18

v

t 1

v

t 2

v

t 3 v

t 4