Question

A cat chase a mouse across a 1.0 m high table. The mouse steps out of the way, and the car slides off the table and strikes the floor 2.2m from the edge of the table. When the car slid off the table what was it’s speed?
Answer is 4.9 m/s how do we get 4.9 m/s?

Answer 1

The cat fell 1.0 m from the ground.

Using the formula

$h = v_{oy}t - \frac{gt^2}{2}$

Here, $v_{oy} = 0, \; h = 1.0 \; m.$

Solving for t, the time it spent in the air is

$t = \sqrt{\frac{2h}{g}} = \sqrt{\frac{2(1.0 \; m)}{9.8 \; m/s^2}} = 0.451753951 \; s$

The cat does not accelerate along the horizontal, so it has constant horizontal velocity. Since it strikes the floor 2.2 m from the table, then

$v_x = \Delta x/t = \frac{2.2\; m}{0.451753951 s} = 4.869907597 \; m/s \Rightarrow 4.9 \; m/s$