A person drops a vertically-oriented, cylindrical steel bar from a height of 4.50 m (measured from the floor to the bottom of the bar). The bar has length = 0.540 m, radius R = 0.750 cm, mass m = 1.300 kg, and Young's modulus Y = 1.000 x 10¹¹ Pa. The bar hits the floor and bounces back up, maintaining its vertical orientation. Use the gravitational acceleration g = 9.81 m/s². Assume that the collision with the floor is elastic, and that no rotation occurs. What is the maximum compression Al of the bar? Al => m

A uniform wire (Y = 2.0 1011 N/m2) is subjected to a longitudinal tensile stress of 4.0 107 N/m2. What is the fractional change in the length of the wire?

Consider a nanotube with a Youngs modulus of 2.130 1012 N/m2 that experiences a tensile stress of 5.3 1010 N/m2. Steel has a Youngs modulus of about 2.000 1011 Pa. How much stress would cause a piece of steel to experience the same strain as the nanotube?

Why is the following situation impossible? A worker in a factory pulls a cabinet across the floor using a rope as shown in Figure P12.36a. The rope make an angle = 37.0 with the floor and is tied h1 = 10.0 cm from the bottom of the cabinet. The uniform rectangular cabinet has height = 100 cm and width w = 60.0 cm, and it weighs 400 N. The cabinet slides with constant speed when a force F = 300 N is applied through the rope. The worker tires of walking backward. He fastens the rope to a point on the cabinet h2 = 65.0 cm off the floor and lays the rope over his shoulder so that he can walk forward and pull as shown in Figure P12.36b. In this way, the rope again makes an angle of = 37.0 with the horizontal and again has a tension of 300 N. Using this technique, the worker is able to slide the cabinet over a long distance on the floor without tiring. Figure P12.36 Problems 36 and 44.