A block sliding down an inclined plane normally accelerates. However, if the friction force increases with speed, then the block can slide at a constant terminal speed in a manner similar to the fall of an object through a fluid. Measurements of the increase in the coefficient of friction for tennis ball cloth sliding on a smooth surface are described over speeds varying by a factor of 9000. For the low speed measurements, the ball cloth was attached to the bottom of a weighted box and pulled along a horizontal surface by a constant horizontal force. Results at higher speeds were obtained by bouncing a tennis ball off the surface.
Topics
Friction
REFERENCES
1.
J.
Ringlein
and M. O.
Robbins
, “Understanding and illustrating the atomic origins of friction
,” Am. J. Phys.
72
, 884
–891
(2004
).2.
J.
Krim
, “Resource Letter: FMMLS–1: Friction at macroscopic and microscopic length scales
,” Am. J. Phys.
70
, 890
–897
(2002
).3.
I. M. Hutchings, Tribology: Friction and Wear of Engineering Materials (Edward Arnold, London, 1992).
4.
P. J. Blau, Friction Science and Technology (Marcel Dekker, New York, 1996).
5.
6.
F.
Heslot
, T.
Baumberger
, B.
Perrin
, B.
Caroli
, and C.
Caroli
, “Creep, stick-slip and dry-friction dynamics
,” Phys. Rev. E
49
, 4973
–4988
(2004
).7.
R.
Morrow
, A.
Grant
, and D. P.
Jackson
, “A strange behavior of friction
,” Phys. Teach.
37
, 412
–415
(1999
).8.
R.
Cross
, “Grip-slip behavior of a bouncing ball
,” Am. J. Phys.
70
, 1093
–1102
(2002
).9.
J.
Witters
and D.
Duymelinck
, “Rolling and sliding resistive forces on balls moving on a flat surface
,” Am. J. Phys.
54
, 80
–83
(1986
).10.
11.
B. N. J. Persson, Sliding Friction (Springer, Berlin, 1998), pp. 395–397.
12.
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© 2005 American Association of Physics Teachers.
2005
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