Answer:
1.98s
Explanation:
The time taken to hit the ground is given by
h=ut+ 1/2 at^2
but u =0
so we have
h=1/2at^2
making t the subject
t=√2h/g
√2×19.6/10
1.98s
The softest sound a human ear can hear is at 0dB. Sounds above 130dB causes pain.
What happens when the light hits the glass depends on what it was in before it hit the glass.
WHILE it's in the glass, the speed of light doesn't change.
