Question

A balloon is going upwards with velocity 12
m/sec. It releases a packet when it is at a
height of 65 m from the ground. How much
time the packet will take to reach the ground
(g=10m/sec)
1) 5 sec 2) 6 sec 3) 7 sec 4) 8 sec

Answer 1

Answer:

a)5 seconds

Step-by-step explanation:

Given,

Take upward direction as -ve and downward direction as +ve.

u=−12m/s

h=65m

g=10m/s ^2

v=0m/s

From 2nd equation of motion,

h=ut+ 1/2 gt^2

65=−12t+ 1/2×10t^2

65=−12t+5t^2

5t^2−12t−65=0

5t(t−5)+13(t−5)=0

t−5=0,5t+13=0

t=− 13/5,5

Time taken to reach the ground is 5sec.