Question

What is the speed of an apple dropped from a tree after 1.5 second ? What distance will it cover during this time ?

Answer 1

when apple dropped from tree , initial speed of Apple is zero
use formula ,
v = u + at
u =0
a = -g m/s^2
t=1.5 sec
v = -3g/2 m/s

hence velocity of Apple is 3g/2 m/s downward .

again ,
use ,
S=ut +1/2 at^2

u =0
t=1.5 s
a= -g m/s^2

S= 0 -1/2 g (3/2)^2 =-(9/8)g m

hence displacement is -(9/8) m
so distance covered by apple is (9/8)m

Answer 2

Answer: [100% CORRECT]

Given: Time of Apple to reach the ground (t) = 1.5 s

           Acceleration due to Gravity (g) = 10 m/s

           Speed of the Apple (v {Final Velocity}) = u + gt

∴Since the Apple is considered as freely falling body, its initial velocity, u = 0

     Now, v = 0 + 10 (1.5)

                 = 10 x 1.5

                 = 15 m/s

∴ The Distance covered during this time,

h = ut + 1/2 gt2

  = 0 (1.5) + 1/2 x 10 x (1.5)2

  = 0 + 5 x (1.5)2

  = 5 x 2.25

  = 11.25 m