Question

An object is thrown vertically upwards and rises to
a height of 10 m. Calculate (i) the velocity with which
the object was thrown upwards and (ii) the time taken
by the object to reach the highest point.​

Answer 1

Answer:

Since an object is thrown vertically upwards, velocity at highest point will be zero and after that it will start falling downwards again. Using this concept,

Now,

i) Using equation of motion,

v^2-u^2=2as

Here, v=final velocity=0m/s; a=-g(since body is travelling against the effect of gravity)

0-u^2=2(-10)(10) {g=10m/s^2}

u=10√2 m/s

ii) v=u+at

here, v=0m/s; a=-g

hence, 0=10√2 -(10)(t)

t=√2s

Cheers!

P.S. For questions of this kind remember maximum height=h=(u^2)/(2g). AND

Time taken to reach maximum height, t=u/g