Answer Happy

Problem 1: Find the centre of mass of a homogeneous disk with radius R, with a circular hole of radius r touching the outer edge of the disk, as shown in the figure. R Problem 2: For a rocket having an initial mass m, and a burn rate of ad, find: a) The minimum exhaust velocity that will allow the rocket to lift off immediately after firing. b) The expression for the burn-out velocity. c) The time the rocket takes to attain the burn-out velocity ignoring g. d) The mass m, of the rocket as a function of rocket velocity.