Question

An object is dropped from a platform 100 feet high. Ignoring wind resistance, how long will it take to reach the ground? _____ s

a 1.8
b 2.5
c 3.2
d 4.5

Answer 1

Answer B is correct.

Step-by-step explanation:

Answer 2

Height of the platform = 100 feet

1 feet = 0.3048 m

100 feet = 30.48 m

Acceleration due to gravity (g) = 9.8 m/s^2

Let the time taken be t

Initial velocity of the object (u) = 0 m/s

Using the seconds equation of motion:

`s = ut + (1)/(2)at^2`

`30.48 = 0 + (1)/(2)* 9.8 * t^2`

`t = \sqrt{(30.48)/(4.9) }`

t = 2.5 seconds

Hence, the option (b) is correct.