Why do some iron objects such as ships float when placed in water while other iron objects such as nails sink? 1. iron ships have large air pockets inside them, making them less dense than water and thus able to float. 2. the same reason that makes planes fly in the sky?

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)

Does anyone know how to solve this problem? i really need . i made an attempt but i just cant get it. a metal rod is 25.000 cm long at 25.0 degrees celsius. when heated to 102.0 degrees celsius, it is 25.054 cm long. what is the coefficient of linear expansion for this metal.

Astronomers studying the planet of rhombus have detected sedimentary rock on its surface. one astronomer wonders if material in this sedimentary rock used to be in igneous rock deep in rhombus’s interior. can igneous rock become sedimentary rock? explain your answer.