An aluminium bar of 8 m length and a steel bar of 5 mm longer in length are kept at 30°C. If the ambient temperature is raised gradually, at what temperature the aluminium bar will elongate 5 mm longer than the steel bar (the linear expansion coefficients for steel and aluminium are 12 × 10-6/°C and 23 × 10-6/°C respectively)?

An aluminium bar of 8 m length and a steel bar of 5 mm longer in lengt

1.	An aluminium bar of 8 m length and a steel bar of 5 mm longer in length are kept at 30°C. If the ambient temperature is raised gradually, at what temperature the aluminium bar will elongate 5 mm longer than the steel bar (the linear expansion coefficients for steel and aluminium are 12 × 10-6/°C and 23 × 10-6/°C respectively)?
A.	50.7°C
B.	69.0°C
C.	143.7°C
D.	33.7°C
Answer» D. 33.7°C