Question

Application of Universal Gravity non-orbital motion Kinetic Energy mp2 Escape velocity EX-11 Find the Minimum speed needed for an object escape form the Earth surface. Gravitational mM Potential Energy U = -G G = 6.67 x 10-11 Work and Energy Woth = AE (2) Conservation of mechanical energy E = E (3) V = 0 Final: object at infinite Ey = y + Ug = źmv} + (-GMT) =0 4 Step procedures of solving work and energy problems Normal force (10) List other forces Friction force (W. - - W, -Parcos Wother 0 0 Water 012) If YES, y zero at infinity y changes? if No, do not need to consider U, 1 YES, compressing/stretching distance Is there a spring? if No, do not need to considers System initial System final Er - Ny+ Ugr + Hop E = E VA 3 Mm +-G Vi =? Initial: at the earth's surface 2GM RE = 11.2 km/s

Answer 1

for object escape Initial PE=0 } e Ei Intial KE = £mv² final PET amm RE } Ee KES r tist £mv²= amm 24 Kg M = mass of earth = 5.97 2x 10 RE= Radius of earth = 6371 X103 m 2 am RE Va 5-972x10 2x 8-67x10 " x (6271x600) vo 1.118 x104 mts m/ V: 11.2 x 10 3 v= 11,2 km/s