Question

An object thrown vertically upwards reaches a height of 800m.What was it's initial velocity? Assume g=10m/s​

Answer 1

Answer:

The answer of the required question asked by you from the chapter kinematics is

4√10 s

Explanation:

Let the initial velocity =u

final velocity = v

v= 0 m/s

s = 800 m

2gs = v square - u square

2 (-10) 800 = u square

u= 40√10 m/s

v= u +at

0=40√10 - 10 t

t = 4√10 s

So the final solution is written below

Hence ,

total time taken by the given object which was thrown vertically upwards = 4√10 sec.

Answer 2

Question:-

An object thrown vertically upwards reaches a height of 800m.What was it's initial velocity? Assume g=10m/s.

Solution:-

Given,

• An object thrown vertically upwards reaches a height of 800m.

We can find the initial velocity by using second equation of motion:-

u = ? ; v = 0 ; s = 800m ; g = -10m/s²

v² - u² = 2as

0² - u² = 2(-10)(800)

-u² = -16000

u = √16000

$\boxed{\bf{\color{yellw}{u \: = \: 126.491106\:m/s}}}$

Verification:-

v² - u² = 2as

0² - 126.491106² = 2(-10)(800)

-16,000 = 16,000