Question

a body is projected vertically up reaches a maximum height of 60m find (a)time of ascent (b) initial velocity (c) time of flight​

Answer 1

$\maltese{\underline{\underline{\sf{\bold{Given\:that:—}}}}}$

A body is projected vertically up reaches a maximum height of 60 cm.

$\maltese{\underline{\underline{\sf{\bold{To\:Find:—}}}}}$

Time of ascent of the body.

Initial velocity of the body.

Time of flight of the body.

$\maltese{\underline{\underline{\sf{\bold{Using\:Formula:—}}}}}$

Formula to find the initial velocity —

${\qquad}{\bigstar}{\boxed{\sf{\bold{ {v}^{2} - {u}^{2} = 2gh}}}}$

Formula to find the time of ascent —

${\qquad}{\bigstar}{\boxed{\sf{\bold{v = u + gt}}}}$

Formula to find the time of flight —

${\quad}{\bigstar}{\boxed{\sf{\bold{time \: of \: flight = time \: of \: ascent + descant}}}}$

$\maltese{\underline{\underline{\sf{\bold{Full\:Solution:—}}}}}$

$\bigstar$According to the Question —

First of all we will find initial velocity so firstly we will use the formula which is given here

${\longrightarrow}{\tt{ - {u}^{2} = 2( - 9.8)60}} \\ \\ {\longrightarrow}{\tt{u = 34.3 \frac{m}{s}}}$

After getting the value of initial velocity.Now we will find the time of ascent so we will use the formula which is given here

${\longrightarrow}{\tt{0 = 34.3 + ( - 9.8)t}} \\ \\ {\longrightarrow} {\tt{t = 3.5 \: sec}}$

After finding the value of time of ascent.Now we will find the value of time of flight so we will use the formula which is given here

${\longrightarrow}{\tt{time \: of \: flight = 3.5 + 3.5}} \\ \\ {\longrightarrow} {\tt{time \: of \:flight = 7 \: sec}}$

Hence,the value of time of flight is 7sec.