The acceleration of gravity is 9.81 m/s 2 . What was the cat’s speed when it slid off the table? Answer in units of m/s.

Question

A cat chases a mouse across a 1.7 m high table. The mouse steps out of the way, and the cat slides off the table and strikes the floor 1.4 m from the edge of the table. The acceleration of gravity is 9.81 m/s 2 . What was the cat’s speed when it slid off the table? Answer in units of m/s.

Answer 1

The equations of horizontal and vertical motion can be solved independently, so it's a two part problem

The Vertical Part

The time it takes to fall 1.7 m is given by

h = ½gt²

so t = √(2h/g) = √((2×1.7)/9.81) = √(3.4/9.81) = 0.589 s

The Horizontal Part

The distance away from the table that the cat lands is given by

d = vt where v is the cat's speed

Since we know d and t we can solve for v by calculating d/t

v = d/t = (1.4 m)/(0.589 s) = 3.1 m/s

(Here I rounded to match the precision of the data given: 2 significant figures.)