Question

An object starting from rest travels 20 m in first 2 seconds and 160 m in next 4 seconds. What will be its velocity after 7 seconds from the start?

Answer 1

distance= 20+160=180m
time= 7secs
initial velocity= 0
final velocity=?
acceleration=?

s=ut+1/2at^2
180=0 (7)+1/2a (7)^2
180=0+1/2a(49)
180=a(24.5)
180/24.5=a
180/24.5 (multiple 10 with 180 and 24.5)=a
1800/245=a
7.3m/s sq=a

to find the final velocity
v=u+at
v=0+7.3(7)
v=51.1m/s

hope this helps u :)