Question

A bricklayer plastering a house falls from an uncompleted building of height 50m calculate time and velocity Use second equation of motion

Answer 1

Given: Height of the building from where bricklayer is falling is 50m

To find: calculate time and velocity of its motion

solution: Here since the bricklayer is falling. therefore we can say that its initial velocity u= 0 m/s

height will be h = 50 m

let us take t as the time taken by it to reach the ground

and v be the velocity with which it will reach the ground

now we know that according to the second law of motion

s = ut + 1/2 at^2

wheres will be the distance and in this question, it will be the vertical height

a is the acceleration and here a will be g that is downward acceleration with which the bricklayer is falling

50 = 0 + 1/2× 10× t^2

t = √10 sec.

Now using the first law of motion

v = u + at

where v is the final velocity

v = 0 + 10(√10)

v = 10√10 m/s

Therefore, we can say that the bricklayer will fall in √10 sec, with the rate of 10√10 m/s.