Question

If a freely falling body travels in the last second a distance equal to the distance travelled by it in the first three seconds, the time of the travel is
1) 6 s 2) 5 s 3) 4 s 4) 3 s​

Answer 1

Answer:

I don't know this answer

Answer 2

Answer:

2 ) 5s

Explanation:

The distance travelled in last second.

Sl∗=u+g2(2t−1)=12×10(2t−1)=5(2t−1)

and distance traveled in first three second,

Sthree=0+12×10×9=45m

According to problem Sl∗=Sthree

⇒5(2t−1)=45⇒2t−1=9⇒t=5 sec