What do you understand by moment of inertia and torque? Word limit 50-60

Please don't copy from any sources. You can rewrite. Plagiarism will be check. Thank you.

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 ?

When considering gravity acceleration and the force of acceleration, what must be true? a. the direction of acceleration must be perpendicular to the direction of the force. b. the direction of the force and the direction of acceleration must be the same as each other. c. the direction of the force and the direction of acceleration must be opposite of each other. d. the mass of the body must be the same as the acceleration of the body.

Which diagram correctly demonstrates the various forces acting on a ball moving horizontally with some speed?