Page 57 - SP015 Past Years PSPM Chapter 6 -14 Ver 2020
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PSPM SP015
PSPM 2010/2011 SF017/2 No. 6
12. A spring stretches by 4 mm when a 1.5 kg mass is suspended at its end. Calculate the
spring constant. [3 m]
PSPM 2010/2011 SF017/2 No. 13(b)
13.
A
5 cm
F 150 cm
B
FIGURE 11.4
A wire AB, of length 150 cm and diameter 1 mm is fixed at both ends. A force F pulls
the wire at the midpoint and causes a displacement of 5 cm as shown in FIGURE 11.4.
If the Young modulus of steel is 2 GPa, calculate the
(a) magnitude of F. [7 m]
(b) energy stored in the wire. [2 m]
PSPM 2011/2012 SF016/2 No. 7(d)
14. A 20.0 kg mass is hung from a 2.0 m long vertical wire. If the wire is elongated by
3.0 mm, calculate the strain energy stored in the wire. [2 m]
PSPM 2012/2013 SF016/2 No. 7(d)(iii)
2
15. A wire fixed to a ceiling has a length of 1.5 m and cross-sectional area 0.2 cm . The
wire stretches by 0.15 cm when a 50 kg load is attached to its free end. Calculate the
Young’s modulus of the wire. [2 m]
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