A 30.0-g object moving to the right at 19.5 cm/s overtakes and collides elastically with a 13.0-g object moving in the same direction at 15.0 cm/s. Find the velocity of each object after the collision. (Take the positive direction to be to the right. Indicate the direction with the sign of your answer.) 30.0-g object Incorrect: Your answer is incorrect. seenKey 16.8 Your response differs significantly from the correct answer. Rework your solution from the beginning and check each step carefully. cm/s 13.0-g object

The final velocity of the 30 g object is 16.8  cm/s

The final velocity of the 13 g object is 21.3 cm/s

Explanation:

Let's study the elastic collision with conservation of linear momentum, assigning object 1 to the 30 g object, and object 2 to the 13 gr object:

so we can write one of the unknowns in terms of the other one:

Now we analyze the equation for conservation of kinetic energy that verifies in elastic collisions:

now we can write this quadratic equation replacing with its expression in terms of and solve it (with the help of a graphing calculator is simpler by looking for the roots).

We get two answers for   : one 15 cm/s, and the other one 21.28 cm/s.

We select the 21.28 cm/s answer since otherwise, the situation is the same as the initial one at which the second object was moving at 15 cm/s.

This velocity can be rounded to one decimal to:  21.3 cm/s

Given the value 21,28 for   , then:

which can be rounded to 16.8 cm/s

float.

archimedes' principle

denser than water sinks in water.

denser than mercury would sink in it