Three objects each have mass m. Each object feels a force from the other two, but not from any other object. Initially the first object is at x=−L, y=0; the second object is at x=+L, y=0; and the third object is at x=0, y=L. The momentum of the system of the particles at the initial time is zero. At a later time the first object is at x=−L/3, y=+L/4; and the second object is at x=+L/2, y=−L. At this later time, where is the third object? Find the x-position of the third object.

a and b sometimes have a positive value

note: the given question is incomplete.

complete question is given below.

which is an example of kinetic energy?

a. the energy stored in ethanol  

b. a hockey puck sliding across the ice  

c. a compressed spring  

d. a ball sitting at the top of a ramp

solution: the kinetic energy is the energy posses by the virtue of the motion of the object.

in the given options, a, c and d are the example of potential energy because it is the energy posses by the virtue of the rest of the object. but option b has the kinetic energy as the object is in motion.

hence, a hockey puck sliding across the ice   is the apex example of kinetic energy.

so, the option (b) a hockey puck sliding across the ice   is the correct option.

+15-35=-20

going in opposite directions