A cylindrical steel rod is originally 250 cm long and has a diameter of 0.254 cm. A force is applied longitudinally and the rod stretches 0.85 cm. What is the magnitude of the force? The value for Young's Modulus for steel is 200*109 Pa. The correct answer is 3400 N, i used the equation F/A=Y(ΔL/L0) but kept getting some weird numbers. I think I'm screwing up on finding the area, since in most of the problems the area is already given. Can someone help me figure this out?