Question

A rock is dropped from a height of 2.5 meters. What is its velocity when it reaches the ground?

a.3.5 meters/second
b.7.0 meters/second
c.12 meters/second
d.14 meters/second
e.49 meters/second

Answer 1

We know, v² - u² = 2as

Here, u = 0 [ Free fall ]

a = 9.8 m/s² [ Constant value for Earth System ]

s = 2.5 m

Substitute their values,

v² - 0 = 2 * 9.8 * 2.5

v² = 49

v = √49

v = 7 m/s

Step-by-step explanation:

Answer 2

We know, v² - u² = 2as
Here, u = 0 [ Free fall ]
a = 9.8 m/s² [ Constant value for Earth System ]
s = 2.5 m

Substitute their values,
v² - 0 = 2 * 9.8 * 2.5
v² = 49
v = √49
v = 7 m/s

In short, Your Answer would be Option B

Hope this helps!