WAEC - Physics (1992 - No. 12)
Steel bars, each of length 3.0 m at 28°C, are to be used for constructing a rail line. If the linear expansivity of steel is 1.0 x 10-5°C, what is the safety gap that must be left between successive bars if the highest temperature expected is 40oC?
1.2 x 10-1cm
8.4 x 10-2cm
7.2 x10-2cm
3.6 x 10-2cm
1.8 x 10-2cm
Explicació
Gap ΔL = αL1Δθ = 1.0 x 10-5 x 3 x (40 - 28)
= 3.6 x 10-2
= 3.6 x 10-2