Problem of objects falling from a height

[Spensy]

A stone falls from the high bridge and reaches the ground in 10 sec, then height of bridge is approximately __________
(a) 590m
(b) 460m
(c) 500m
(d) 1000m



the object falling has an acceleration due to gravity of 9.8m/s^2 and it reaches the ground in 10 secs so the using the formula. S= vit+1/2at^2
where vi = to zero , a=9.8m/s^2 and time t = 10secs

S = 0*10+1/2(9.8)(10)^2
S = 4.9*100
S = 490
S = 500m approximately.

Am i Correct ?

 

[Doc Al]

Looks good.

(But please use the https://www.physicsforums.com/forumdisplay.php?f=153" for questions like this.)

 

[elabed haidar]

height = 0.5 times acceleration times (time to the power 2) since initial velocity =0

 

[Doc Al]

height = 0.5 times acceleration times (time to the power 2) since initial velocity =0

I think the OP is aware of this--since that very formula was shown in the first post.