Question

Your friend drops your house keys down to you from their second floor window. If you catch them 2.4 m from where your friend dropped them, what is the velocity of the keys when you catch them?

a.
-6.9 m/s
c.
-7.2 m/s
b.
-6.5 m/s
d.
-7.4 m/s

Answer 1

6.9m/s

Step-by-step explanation:

Given parameters:

Initial velocity = 0m/s

Height = 2.4m

Unknown:

Final velocity = ?

Solution:

To solve this problem, we use the kinematics equation below:

v² = u² + 2gh

v is the final velocity

u is the initial velocity

g is the acceleration due to gravity = 9.8m/s²

h is the height

v² = 0² + (2 x 9.8 x 2.4)

v = 6.9m/s