Answer:
0.73 s
Step-by-step explanation:
The glass is in free fall, so its vertical position at time t is given by the equation:
![y(t) = h + ut + (1)/(2)gt^2](https://img.qammunity.org/2020/formulas/physics/middle-school/lojahgfcc4fzourjmnrfzip54mfvir9ryo.png)
where
h = 2.6 m is the initial height
u = 0 is the initial velocity of the glass
is the acceleration of gravity (downward since it is negative)
We want to know the time t at which the glass reaches the ground, so when
y(t) = 0
So the equation becomes
![0 = h + (1)/(2)gt^2](https://img.qammunity.org/2020/formulas/physics/middle-school/jcy861w2lk4sa00741a60kz38ppp44ooiv.png)
And solving for t, we find
![t=\sqrt{(-2h)/(g)}=\sqrt{(-2(2.6))/(-9.8)}=0.73 s](https://img.qammunity.org/2020/formulas/physics/middle-school/uaa7mdb2cpdp6ljp7aamuqllcfhifwylr0.png)