A300-kg piano being held by a crane is accidentally dropped from a height of 15 meters. a. what is the speed of the piano just before it hits the ground? b. how much energy is dissipated when the piano hits the ground? c. what are some indicators of this release of energy that could be observed during and shortly after the piano hits the ground? d. suppose that a parachute is used to slow the fall of the piano. i. how would the amount of kinetic energy dissipated by the ground change? explain. ii. how would the total amount of energy dissipated change? explain.

Ateam of astronauts is on a mission to land on and explore a large asteroid. in addition to collecting samples and performing experiments, one of their tasks is to demonstrate the concept of the escape speed by throwing rocks straight up at various initial speeds. with what minimum initial speed vesc will the rocks need to be thrown in order for them never to "fall" back to the asteroid? assume that the asteroid is approximately spherical, with an average density p 3.84 x108 g/m3 and volume v 2.17 x 1012 m3 recall that the universal gravitational constant is g 6.67 x 10-11 n m2/kg2

Increasing the pressure on one spot of a fluid will increase the pressure everywhere else in the fluid a. pascals principal b. archimedes' principal c. bernoulli's principal

Two conductors, a and b, are each in the shape of a tetrahedron. but of different sizes. they are charged in the following manner: 1. tetrahedron a is charged from an electrostatic generator to charge q. 2. tetrahedron a is briefly touched to tetrahedron b. 3. steps 1 and 2 are repeated until the charge on tetrahedron b reaches a maximum value. if the charge on tetrahedron b was q/4 after the first time it touched tetrahedron a. what is the final charge qbmax on tetrahedron b?