The Architect of a Trendy New Inner-City Townhouse in Adelaide

Multiple Choice

The architect of a trendy new inner-city townhouse in Adelaide wants a staircase where the steps stick out from a wall and are only supported at the wall end. If each step is made of steel and is 1.5 cm thick, 30 cm wide and 1.2 m wide, and a person weighing 120 kg stands on the end of them, by how much will the end of the step bend? Young's modulus for steel is 2.0x1011 N m-2.

A) 10 cm.
B) 7 cm.
C) 4 cm.
D) 1 cm.
E) 0.5 cm.