An 0.80-kg block is held in place against the spring by a 67-n horizontal external force (see the figure. the external force is removed, and the block is projected with a velocityv1 = 1.2 m/s upon separation from the spring. the block descends a ramp and has a velocity v2 = 1.9 m/s at the bottom. the track is frictionless between points a andb. the block enters a rough section atb, extending toe. the coefficient of kinetic friction over this section is 0.39. the velocity of the block isv3 = 1.4 m/s atc. the block moves on tod, where it stops. the spring constant of the spring is closest to

Three different objects, all with different masses, are initially at rest at the bottom of a set of steps. each step is of uniform height . the mass of each object is a multiple of the base mass : object 1 has mass 4..00m , object 2 has mass 1..96m , and object 3 has mass . when the objects are at the bottom of the steps, define the total gravitational potential energy of the three-object system to be zero. if the objects are then relocated as shown, what is the new total potential energy of the system? each answer requires the numerical coefficient to an algebraic expression. each algebraic expression is given using some combination of the variables , , and , where is the acceleration due to gravity. enter only the numerical coefficient. (example: if the answer is 1..23mgd , just enter 1.23)

What is a good example of instantaneous speed

Which body is in equilibrium? (1) a satellite orbiting earth in a circular orbit (2) a ball falling freely toward the surface of earth (3) a car moving with a constant speed along a straight, level road (4) a projectile at the highest point in its trajectory