Question

a body is thrown upward with velocity hundred metre per second and it travels for 5 m in the last second of its upward journey .if the same body is thrown upward with velocity 200 m per second what distance will it travel in the last second of upward journey ( g = 10 M per second square)

Answer 1

A vertically projected up body always travels a distance of g/2 in last second of its free fall irrespective of velocity of projection.

∴ Distance travelled in last second of upward journey when it was projected with 200 m/s will also be 5 m

Answer 2

ANSWER

For case 2 there is no effect of case 1.

For case 2 there is no effect of case 1.Now ,

V2=u2−2gS

0=2002−2⋆10⋆S

40000/20=S

S=2000 metres

V=u+g⋆t

0=200−10⋆t

t=20sec

In last second distance,

S20=u+(1/2)g⋆(2t−1)

=200−(1/2)⋆10⋆39

=200−195

=5 metres.

thank you