decelerating cars - kypt
DESCRIPTION
Experiment presentation for the selection for 혜움나래, KMLA's club for KYPT and IYPT preparationTRANSCRIPT
DECELERATING CARS
KangSan Kim혜움나래
Problem Statement
1. Simple skid2. reverse
Existing theoretical background𝜇𝑘
velocity
fric
tion
Experiment setup - 1
Experiment setup - 2
Raw dataForce Time (seconds per 10 crank revolutions)
0.4 14.59 12.31 11.89
0.5 6.4 7.07 6.68
0.6 5.29 6.44
Force Time0.7 18.56
0.8 15.44
0.9 10.62
1.1 7.7
Calibrated data
0 0.2 0.4 0.6 0.8 1 1.2 1.40
0.2
0.4
0.6
0.8
1
1.2
f(x) = 0.604012555561476 x + 0.409807867815422
f(x) = 0.224102928041391 ln(x) + 0.956165805589757f(x) = 0.981458167467079 x^0.341889476070784f(x) = − 0.179906476199951 x² + 0.807388417596375 x + 0.382199699370392
velocity
Fric
tiona
l for
ce
Calibrated data
0 0.2 0.4 0.6 0.8 1 1.2 1.40
0.2
0.4
0.6
0.8
1
1.2
f(x) = 0.604012555561476 x + 0.409807867815422
f(x) = 0.224102928041391 ln(x) + 0.956165805589757f(x) = 0.981458167467079 x^0.341889476070784
f(x) = − 0.179906476199951 x² + 0.807388417596375 x + 0.382199699370392
velocity
Fric
tiona
l for
ce
Explanation #1
0 0.2 0.4 0.6 0.8 1 1.2 1.40
0.2
0.4
0.6
0.8
1
1.2
f(x) = 0.604012555561476 x + 0.409807867815422
velocity
Fric
tiona
l for
ce
Explanation #1
time
forc
e
Δ 𝑡 Δ 𝑡 ′
Explanation #2
0 0.2 0.4 0.6 0.8 1 1.2 1.40
0.2
0.4
0.6
0.8
1
1.2
f(x) = 0.224102928041391 ln(x) + 0.956165805589757f(x) = 0.981458167467079 x^0.341889476070784
velocity
Fric
tiona
l for
ce
Explanation #3
0 0.2 0.4 0.6 0.8 1 1.2 1.40
0.2
0.4
0.6
0.8
1
1.2
f(x) = 0.224102928041391 ln(x) + 0.956165805589757f(x) = 0.981458167467079 x^0.341889476070784
velocity
Fric
tiona
l for
ce
Intimate contact
Fast Passover
Handicapso Experiments at lower velocity
o To determine the linear character of the graph
oMeasuring apparatus’ low accuracy
o Experiments at higher velocityo The change of slope at
extreme velocitiesoMechanical failure of cheap
elements
Conclusion• Conventional physics• Coefficient is constant regardless of situations• Horizontal line graph
• NOT a horizontal line
• 3 experimental solutions:• Linear• Decreasing slope• Decreasing, and then increasing slope