The figure shows a steel piece of diameter 20 mm at A and C, and 10 mm at B. The lengths of three sections A, B and C are each equal to 20 mm. The piece is held between two rigid surfaces X and Y. The coefficient of linear expansion α = 1.2 × 10-5 /°C and Young’s modulus E = 2 × 105 MPa for steelWhen the temperature of this piece increases by 50 °C, the stresses in sections A and B are

The figure shows a steel piece of diameter 20 mm at A and C, and 10 mm

1.	The figure shows a steel piece of diameter 20 mm at A and C, and 10 mm at B. The lengths of three sections A, B and C are each equal to 20 mm. The piece is held between two rigid surfaces X and Y. The coefficient of linear expansion α = 1.2 × 10-5 /°C and Young’s modulus E = 2 × 105 MPa for steelWhen the temperature of this piece increases by 50 °C, the stresses in sections A and B are
A.	120 MPa and 480 MPa
B.	60 MPa and 240 MPa
C.	120 MPa and 120 MPa
D.	60 MPa and 120 MPa
Answer» B. 60 MPa and 240 MPa