A50-mg boxcar a is moving in a railroad switchyard with a velocity of 10 km/h toward cars b and c, which are both at rest with their brakes off at a short distance from each other. car b is a 25-mg flatcar supporting a 40-mg container, and car c is a 45-mg boxcar. as the cars hit each other, they get automatically and tightly coupled. determine the velocity of car a immediately after each of the two couplings, assuming that the container does not slide on the flatcar.

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.

multiple allele inheritance is traits controlled by more than 2 alleles (ex: pigeons having 3 alleles of one gene govern their feather color).