4. A stone is dropped from the fifth floor of a building from a height 14 m. How long would it take for the stone to hit the ground?
I

1.690308509s

Explanation:

v²=u²+2as

v²=0²+2(9.8)(14)

v²=274.4

∴v=16.56502339m/s

v=u+at

16.56502339=0+9.8t

∴t=1.690308509s

answer: the correct answer id option(d).

explanation:

snell's law refraction:

the angle of refraction =

the angle of incidence =

refractive index of air = = 1

refractive index of glycerol = 1.47

from the given options, the most closest answer to 63.72° is 65° of option (d).

measuring things 1 litre of water