Question

when a ball a is thrown in vertically upward direction with velocity 20m/s-¹ exactly at the same time is allowed to fall freely from height h the magnitude of velocity a with respect to b 2s is ___ms-¹(g=10m/s²
a)40
a)10
c)20
d)30​

Answer 1

when a ball a is thrown in vertically upward direction with velocity 20m/s-¹ exactly at the same time is allowed to fall freely from height h the magnitude of velocity a with respect to b 2s is ___ms-¹(g=10m/s²

$\red{\bold{\underline{\underline{SolutiOn:}}}}$

(a) Thking vertical upward motion of ball upto highest point, we have <br>

, <br>

<br> As,

<br> :. 0=20^(2) =2 (-10) S

S= (20 xx 20)/(2xx 10) =20 m

v=u + at

0= 20 + (-10) t_(1) or t_(1) =2 s

u=o ms^(-1) , a=10 m//s^(2),

S=20 +25 =45 m , t=t_(2) (say)

S=ut + 1/2 at^(2)

45 =0 +1/2 xx 10 xx t_(2)^(2)

t_(2) = ((2xx 45)/(18)) ^(1//2) =3 s

= t_(1) +t_(2) 2+3 =5 s

Answer 2

Answer:

b) 10 m/s is the answer