Acat named schrödinger walks along a uniform plank that is 4.00 m long and has a mass of 7.00 kg. the plank is supported by two sawhorses, one that is 0.44 m from the left end of the plank, and the other that is 1.50 m from the right end. when the cat reaches the very right end of the plank, the plank starts to tip. what is schrodinger’s mass? note: just when the plank begins to tip, the normal force on the plank from the sawhorse on the left will go to zero.

Many machines- including inclined planes such as ramps- increase the strength of the force put into the machine but decrease the distance over which the force is applied.

Samir watches a 100-minute movie on his spaceship. maria's spaceshipe flies in the same direction as samir's spaceship but she observes his move to last 125 minutes and his spaceship to be 40 m long. how long does samir observe his own spaceship to be? according to an observer on earth, planet x is stationary. maria and samir depart earth on their spaceships at the same time, each flying at 0.5c. maria flies toward planet x and samir flies in the opposite direction. according to maria, her voyage to planet x takes 9 years. how many years does marias voyage take according to samir?

Consider a system to be two train cars traveling toward each other. what is the total momentum of the system before the train cars collide?   kg • what must the total momentum of the system be after the train cars collide?   kg •