Question

A particle is projected from ground with speed QOjm/
s at an angle 30° with horizontal from ground. The
magnitude of average velocity of particle in time
interval / = 2 s to t = 6s is pake g = 10 m/s2]
(1) 40^/2 m/s (2) 40 m/s
(3) Zero (4) 40^/3 m/s

Answer 1

Given, u = 80 m/s
θ = 300
Distance travelled by the particle along horizontal direction in t = 2 s is given by :
x1 = u cos θ t1
x1 = 80 X cos 300 X 2 = 80 √3 m.

Distance travelled by the particle along horizontal direction in t = 6 s is given by :
x2 = u cos θ t2
​x2 = 80 X cos 300 X 6
= 240 √3 m


​Magnitude of avg. velocity of particle in time t = 2 s to t = 6 s is :
v = Δx/Δ t = x2 − x1/t2 − t1
 = 240 √3 − 80 √3/6−2
 = 40√3m/s