Page 64 - SP015 Past Years PSPM Chapter 6 -14 Ver 2020

PHYSICS PSPM SEM 1 1999 - 2017

PSPM 2009/2010 SF017/2 No. 7(b)

24.

1.5 m

gap = 5.0 mm (the scale is exaggerated)

FIGURE 12.6

A 1.5 m steel rod is attached to a fixed wall as shown in FIGURE 12.6. At 30 C, a gap
between the rod and the opposite wall is 5.0 mm. By neglecting the expansion of the
walls, at what temperature will the gap close? The coefficient of linear expansion for
-1
-6
steel is 12 × 10 C . [3 m]

PSPM 2011/2012 SF016/2 No. 8(a)(ii)

25. A pair of eyeglass frame is made of epoxy plastic. At 20 C, the frame has circular lens
holes of radius 2.20 cm. If the coefficient of linear expansion of the epoxy is
-1
-4
3.0  10 C , to what temperature must the frame be heated so that a lens of radius
2.21 cm fits the frame? [3 m]

PSPM 2012/2013 SF016/2 No. 8(b)

26. The length of a metal bar is 300 cm at –30 C. Given the coefficient of linear expansion
-6
-1
of the metal bar is 11  10 C , calculate the length of the bar at 80 C. [3 m]

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