Question

A particle in free-fall:

a) takes 42 seconds to travel 490 meters at g=9.8 m/s2
B) takes 15.8 seconds to travel 490 meters at g= 9.8 m/s2
C) takes 4.5 seconds to travel 490 meters at g= 9.8 m/s2
D) takes 10 seconds to travel 490 meters at g= 9.8 m/s2

Answer 1

Given
u=0
h=490m
g=9.8m/s^2
t=?

Answer 2

Use
h=ut+.5gt^2

Answer 3

ok thanks

Answer 4

Can u tell me the right option?

Answer 5

Anyway welcome!!

Answer 6

No its not B

Answer 7

Vf = Vi + at

you know everything except t. solve for t.

Answer 8

sorry, also use vf^2 - vi^2 = 2aX

Answer 9

the answer is not B...its 9.9 sec so its D