Comic-book superheroes are sometimes able to punch holes through steel walls. (a) if the ultimate shear strength of steel is taken to be 2.50 x 108 pa, what force is required to punch through a steel plate 2.00 cm thick? assume the superhero’s fist has cross-sectional area of 1.00 x 102 cm2 and is approximately circular. (b) qualitatively, what would happen to the superhero on delivery of the punch? what physical law applies?

Three different objects, all with different masses, are initially at rest at the bottom of a set of steps. each step is of uniform height . the mass of each object is a multiple of the base mass : object 1 has mass 4..00m , object 2 has mass 1..96m , and object 3 has mass . when the objects are at the bottom of the steps, define the total gravitational potential energy of the three-object system to be zero. if the objects are then relocated as shown, what is the new total potential energy of the system? each answer requires the numerical coefficient to an algebraic expression. each algebraic expression is given using some combination of the variables , , and , where is the acceleration due to gravity. enter only the numerical coefficient. (example: if the answer is 1..23mgd , just enter 1.23)

Find v(t), given acceleration a(t)=7j and initial velocity v(0)=k

Arope has one end tied to a vertical support. you hold the other end so that the rope is horizontal. if you move the end of the rope back and forth with a frequency of 4 hz, the transverse wave you produce has a wavelength of 0.5 m. what is the speed of the wave in the rope?