ticker tapes

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Ticker TapesTicker Tapes

K WarneK Warne


ApparatusApparatus Trolley & trackTrolley & track Inclined planeInclined plane Ticker timerTicker timer Ticker tapeTicker tape Power sourcePower source

Compensating for frictionCompensating for friction

• Connect up the trolley, tape and ticker timer.Connect up the trolley, tape and ticker timer.• Start the timer.Start the timer.• Gently push the trolley down the slope.Gently push the trolley down the slope.• Stop the timer when the trolley hits the end of the track.Stop the timer when the trolley hits the end of the track.• Examine the ticker tape.Examine the ticker tape.• Set the angle of the slope so that with a Set the angle of the slope so that with a gentle pushgentle push the trolley will the trolley will

move down the slope with move down the slope with constant velocityconstant velocity. (Evenly spaced dots). (Evenly spaced dots)


Ticker Tape - calculationsTicker Tape - calculations

Analysis of the tapes Analysis of the tapes Note the Note the frequencyfrequency of the timer. of the timer.• Discard the beginning and end of the tapes (unevenly spaced dots).Discard the beginning and end of the tapes (unevenly spaced dots).• Mark off TWO lengthslengths or or intervalsintervals..• Any Any unevenuneven number of dotsnumber of dots (even no. of spaces) will work best.• Label these intervals Label these intervals A - BA - B and and C - DC - D• The distance between the intervalsdistance between the intervals does not matter but you must be able to

see the dots clearly.• Measure the Measure the displacementdisplacement (distance from first to last dot) across EACH (distance from first to last dot) across EACH

INTERVAL (INTERVAL (SSA-BA-B, S, SC-DC-D).).• Find and label the Find and label the MIDPOINTSMIDPOINTS (dot 3) of each interval A – B & C – D – (dot 3) of each interval A – B & C – D – x x

and yand y respectively. respectively.• Count the Count the number of spacesnumber of spaces between between x and y.x and y.

... . . . . . . . . . . . . .

SLOW Tape moves to LEFT FAST!



If frequency = 50 Hz .: Period = 1/50 = 0.02s

Time for Interval (A-B) = spaces x period = 4 x 0.02 = 0.08s

1 2 3 4 Spaces

( X – Y) Frequency of timer: 50 Hz Period of Timer = 1/FREQUENCY

... . . . . . . . . . . . . . X XA B C D

SSA-BA-B SSB-CB-C

1 2 3 4 5 Dots

ww xx yy

INTERVALINTERVAL SpacesSpaces Time (s)Time (s) Displacement Displacement (m)(m)

Average Average Velocity Velocity

(m/s)(m/s)

Inst. Inst. Velocity Velocity

at...at...

Change in Change in VelocityVelocity

Time Time (s)(s)

Acceleration Acceleration (m.s(m.s-2-2))

A-BA-B WWWWXX WWXX WWXX

B-CB-C XX

C-DC-D YYXXYY XXYY XXYY

D-ED-E ZZYYZZ YYZZ YYZZ

44

44

44

0.080.08

0.080.08

0.080.08

0.0230.023

0.0500.050

0.1000.100

0.023/0.080.023/0.08

= 0.2875= 0.2875

0.05/0.080.05/0.08

= 0.625= 0.625

0.1/0.080.1/0.08

= 1.25= 1.25

0.63 – 0.290.63 – 0.29

=0.34=0.34

m.sm.s-1-1

0.080.080.33750.3375

0.080.08

= 4.22= 4.22



Displacement (S) = Distance from first dot to last dot.

VELOCITY = DisplacementDisplacement (m)

timetime (s)= (m.s-1)

ACCELERATIONACCELERATION = Inst. Velocity (m/s)

timetime (s)=

v2 - v1

tt2-12-1

timetime = no of spacesspaces x time for each spacespace (period)

Frequency of timer: ______ Period of Timer: _______________________

INTERVALINTERVAL SpacesSpaces Time Time (s)(s)

Displacement Displacement (m)(m)


(m/s)(m/s)


at...at...

Change Change in in

VelocityVelocity

Time Time (s)(s)


A-BA-B WW WWXX WWXX WWXX

B-CB-C XX

C-DC-D YY XXYY XXYY XXYY

D-ED-E ZZ YYZZ YYZZ YYZZ

……

(m.s-2)


Ticker Tape GraphsTicker Tape GraphsPlot graphs on the of Plot graphs on the of DISPLACEMENT(mDISPLACEMENT(m)) against against TIMETIME(s)(s) on the same system of on the same system of

axis for axis for each tapeeach tape made. made.

Do the same for and Do the same for and VELOCITYVELOCITY (m/s) against (m/s) against TIMETIME (s) and (s) and ACCELERATIONACCELERATION against

TIMETIME . .

... . . . . . . . . . . . . . X

A B C DSSxx SSyy

ww xxt1

t2

s (m)

t (s)t1 t2 ect…

SSww

SSxx

v (m.s-1)

t (s)t1 t2 ect…

vvww

vvyy

PointPoint TimeTime(s)(s)

Disp. Disp. (m)(m)

Ins. Ins. VV (m.s(m.s-1-1))

WW

XX

yy


Constant Velocity - calculationsConstant Velocity - calculations

LengLengthth

Time/Time/(s)(s)

Displacement Displacement /(m)/(m) VelocityVelocity

II 00 00 00

IIII 0.60.6 0.170.170.170.17

0.60.6

IIIIII 1.21.2 0.350.350.35-0.170.35-0.17

1.2-0.61.2-0.6

IVIV 1.81.8 0.520.520.52-0.350.52-0.35

1.8-1.21.8-1.2

t

v

t

s


Acceleration - GraphsAcceleration - Graphs

t

s (m)

Displacement vs. time

t (s)x x

x

x v (m/s)

t (s)

x x x

x x

Line of best fitX

a (m/s2)

t (s)

INTERVALINTERVAL SpacesSpaces Time Time (s)(s)

Displacement Displacement (m)(m)


(m/s)(m/s)


at...at...

Change Change in in

VelocityVelocity

Time Time (s)(s)


A-BA-B 44 0.080.08 0.0230.0230.023/0.080.023/0.08

0.28750.2875 WWWWXX

0.625 – 0.625 – 0.28750.2875

=0.3375=0.3375

WWXX

0.080.08WWXX

0.33750.3375

0.080.08

= 4.218= 4.218B-CB-C 44 0.080.08 0.0500.0500.05/0.080.05/0.08

0.6250.625XX

constantSmooth curve

Velocity vs. time Acceleration vs. time


VELOCITY FROM S v T GraphVELOCITY FROM S v T GraphDisplacement vs. time

s (m)

t (s)

x

x

x

x

A B C D E

Tangent (only touches curve at ONE POINT

GRADIENT

m = Change in Y

Change in X

(x1, y1)

(x2, y2)

Y2-y1

x2-x1=

x1

y1

Gradient of the displacement - time graph gives the INSTANTANEOUS VELOCITY at that point.

= velocity at. D

x2

y22

1


Hi -Hi -

This is a This is a SAMPLESAMPLE presentation only. presentation only.

My FULL presentations, which contain loads more slides and other resources, are freely My FULL presentations, which contain loads more slides and other resources, are freely available on my resource sharing website:available on my resource sharing website:

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Have a look and enjoy!Have a look and enjoy!

Keith WarneKeith Warne

ticker tapes

Education

sm t s x x x x

x x abcd s

s w s x

x abcd s x s y w x t

s spaces x y

dots w x time x y

b c d x

b s bc