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A 129-kg horizontal platform is a uniform disk of radius 1.6…

A 129-kg horizontal platform is a uniform disk of radius 1.61 m and can rotate about the vertical axis through its center. A 65.7-kg person stands on the platform at a distance of 1.07 m from the center and a 27.3-kg dog sits on the platform near the person, 1.31 m from the center. Find the moment of inertia of this system, consisting of the platform and its population, with respect to the axis.

Dr. Evil and his henchmen intend to deflect the Moon from it…

Dr. Evil and his henchmen intend to deflect the Moon from its orbit around Earth by pulling it with a force of 3130 N. They plan to accomplish this by placing a mini black hole 6.17 x 106 m from the center of the Moon and letting gravitation do what gravitation does. What must the mass of the mini black hole be for the evil scheme to succeed? The mass of the Moon is 7.36 × 1022kg.  G = 6.673 x 10-11 N m2/kg2

A block is attached to a spring which is resting on a fricti…

A block is attached to a spring which is resting on a frictionless table. The block is pushed into the spring, compressing it.  The graph shows the component of the force (in N) exerted by the spring back on the block versus the position of the block relative to equilibrium.  What is the energy stored in the spring when it is pushed back to a distance of 4.5 cm from equillibrium? 

I. Answer the following questions in Spanish: 1.  ¿Quién era…

I. Answer the following questions in Spanish: 1.  ¿Quién era tu maestro favorito en la escuela primaria?  ¿En qué grado estabas y por qué te gustaba? 2.  ¿Cuál era tu programa favorito de tele cuando eras niño/a? 3.  ¿Qué hacías los fines de semana como niño/a? 4.  ¿Cuántos años tenías en 2015 (dos mil quince)? 5.  ¿Cuál era tu canción favorita cuando eras niño/a? II.  Make a voice recording to record your answers  and submit here