Aspaceship of mass m has its engines switched off and is moving in a circular orbit at height r above the surface of a planet of mass m and radius r. a) derive an expression for total mechanical energy e of the orbiting spaceship, in terms of g, m, m and r. b) derive an expression for the minimum speed v the spaceship would need to escape from this orbit into deep space, in terms of system parameters. (the engines can’t fire for the whole trip; they can only give the spaceship one boost so it obtains this velocity. ignore all other celestial objects.)

Which of the following harmful chemicals are found in tobacco smoke? a. carbon monoxide b. carbon dioxide c. nicotine b. carbon dioxide d. both a and c

Which is the best predictor of the radioactive nature of an isotope? o the proton-to-electron ratio the neutron-to-proton ratio o the neutron-to-electron ratio the electron-to-proton ratio

High schoolphysics 5+3 pts a neon light consists of a glass tube with metal wires at each end. when connected to a high-voltage source, the gas glows. if a fly lands on the glass tube, what will most likely happen? a) the fly will not feel a shock because the glass conducts any free electrons back into the gas. b) electrons will flow directly from the metal wires along the glass and shock the fly. c) the fly will not feel a shock because the glass insulates it from the electrons in the gas and the metal. d) electrons that are moving through the gas will be conducted through the glass and shock the fly.