Answer:
The ball took 0.4 seconds
Explanation:
» From the second newton's equation of motion.
[tex]{ \boxed{ \tt{s = ut + \frac{1}{2} {gt}^{2} }}}[/tex]
- s is displacement, s = 80cm, s = 0.8 meters
- u is initial velocity, u = 0 [ from rest ]
- g is 10 m/s²
[tex]{ \tt{0.8 = (0 \times t) + ( \frac{1}{2} \times 10 \times {t}^{2} )}} \\ \\ { \tt{0.8 = 5 {t}^{2} }} \\ { \tt{ {t}^{2} = 0.16 }} \\ { \tt{t = \sqrt{0.16} }} \\ \\ { \underline{ \underline{ \tt{ \: time = 0.4 \: seconds \: \: }}}}[/tex]
