Caleb wants to create a block and tackle pulley system that lift a 500 N weight when a 100 N weight is attached. How many segments of rope should be attached to the block and tackle

Agymnast dismounts off the uneven bars in a tuck position with a radius of 0.3m (assume she is a solid sphere) and an angular velocity of 2rev/s. during the dismount she stretches out into the straight position, with a length of 1.5m, (assume she is a uniform rod through the center) for her landing. the gymnast has a mass of 50kg. what is her angular velocity in the straight position?

The free body diagram shows a box being pulled to the left up a 25-degree incline. the magnitude of the normal force is

Consider a system with two masses that are moving away from each other. why will the kinetic energy differ if the frame of reference is a stationary observer or one of the masses?