When a 2.60-kg object is hung vertically on a certain light spring described by hooke's law, the spring stretches 2.86 cm. (a) what is the force constant of the spring? n/m (b) if the 2.60-kg object is removed, how far will the spring stretch if a 1.30-kg block is hung on it? cm (c) how much work must an external agent do to stretch the same spring 7.50 cm from its unstretched position?

On a horizontal frictionless surface, a small block with mass 0.200 kg has a collision with a block of mass 0.400 kg. immediately after the collision, the 0.200 kg block is moving at 12.0 m/s in the direction 30° north of east and the 0.400 kg block is moving at 11.2 m/s in the direction 53.1° south of east. use coordinates where the +x-axis is east and the +y-axis is north.(a) what is the total kinetic energy of the two blocks after the collision (in ) what is the x-component of the total momentum of the two blocks after the collision? (indicate the direction with the sign of your ) what is the y-component of the total momentum of the two blocks after the collision? (indicate the direction with the sign of your answer.)