Question

An object falls 210 m in 6.3 s. What was it's initial velocity? Express your answer with the correct number of significant digits.

Answer 1

`u = 2.5 \ m/s`

Step-by-step explanation:

Given data:

Height,
`h = 210 \ m`

Time,
`t = 6.3 \ s`

Let the initial velocity of the object be u.

From the kinematic equation,

`h = ut + (1)/(2)gt^(2)`

`210 = u * 6.3 + 0.5 * 9.80 * (6.3)^(2)`

`\Rightarrow \ u = 2.46 \ m/s`

`u = 2.5 \ m/s` (rounding to tenth place)