Question

A body is projected vertically upwards with a speed ‘u’. Find the (a) time taken and (b) the distance travelled by the body in reaching the topmost point. Take a= -g.

Answer 1

Answer:

(a) t = u/g

(b) Distance travelled = (u^2/g) - (u^2/2g)

Explanation:

(a)When it reaches its topmost point...the final speed v = 0...;

Apply the formula.... v = u + at

; 0 = u + (-g)t

So hence the time taken to reach the top most point....; t = u/g

(b)Apply the formula...s = ut + 1/2at^2

where s is the distance travelled

also substitute t with the answer in (a)

s = u(u/g) + 1/2(-g)(u/g)^2

s = (u^2/g) - (u^2/2g)