Question

A balloon powered car is shot horizontally off the end of a 2.7 m high table at 5.5 m/s. How far horizontally from the edge of the desk does the car land?

Answer 1

Time of falling $t$ can be found from the kinematic equation (if there is no vertical initial velocity component):

$$h = \dfrac{gt^2}{2}$$

where $h = 2.7m$ is the table height, and $g = 9.81m/s^2$ is the gravitational acceleration. Thus, obtain:

$$t = \sqrt{\dfrac{2h}{g}} = \sqrt{\dfrac{2\cdot 2.7}{9.81}} \approx 0.74s$$

In this time the survival kit covers the following horizontal distance:

$$d = v_0t = 5.5m/s\cdot 0.74s \approx 4.1m$$

Here $v_0 = 5.5m/s$ is the initial horizontal velocity of the car.

Answer. 4.1 m.