The radius of earth is 6370km and of mars is 3400km. if an object weighs 200n or earth , what will be it's weight on mars. the mass of mars is 0.11 that of earth.

Adiver in midair has an angular velocity of 6.0 rad/s and a moment of inertia of 1.2 kg·m2. he then pulls is arms and legs into a tuck position and his angular velocity increases to 12 rad/s. the net external torque acting on the diver is zero. what is his moment of inertia in the tuck position?

The boy of mass 30 kg is at r1= 2 meters from the fulcrum. of the girl is 45 kg, at what r2 must she sit so that they are balanced ?

Anybody wanna ? (picture included? )