Question

A 5.0 kg of object is dropped from height of 2.5 m above the floor. What is the object's momentum after 2.5s. 

Answer 1

The speed of object after 2.5 second is given by

$$v= u+gt$$

Where $u$ is initial speed that is zero,$g$ is acceleration due to gravity that is 9.8 m-s^-2 and $t$ is time taken that is 2.5 sec.Thus

$$v=gt \\v=9 .8×2.5\\v=24.5 m/s$$

Now momentum of object is

$$p=mv\\p=5×24.5N/s\\p=122.5 N/s$$

Thus momentum of object is 122.5N/s