Question

A marble rolls off a table from a height of 1.5 meters. Approximately how much time was the marble in the air?

O 1.1 seconds
O 0.78 seconds
O 0.55 seconds
O 0.2 seconds

Answer 1

t = 0.55 s

Step-by-step explanation:

Given that,

Height of the marble, h = 1.5 m

We need to find the time for which the marble is in air. Let the time is t. Using second equation of motion to find it as follows :

`h=ut+(1)/(2)at^2`

Here, u = 0 and a = g

`h=(1)/(2)gt^2\\\\t=\sqrt{(2h)/(g)} \\\\t=\sqrt{(2\cdot1.5)/(9.8)}\\\\t=0.55\ s`

So, the marble is in air for 0.55 s. Hence, the correct option is (c).