Question

A helicopter’s speed increases from 25 m/s to 60 m/s in 5 seconds. What is the acceleration of this helicopter?

Answer 1

The answer is `"7 m/s"^2`.

Explanation:

`"Acceleration"` `= ("final speed " - " initial speed")/"time"`

So

`a = ("60 m/s " - " 25 m/s") / "5 s"`

`a = "35 m/s" / "5 s"`

`a = "7 m/s"^2`

Answer 2

`7 \ "m/s"^2`

Explanation:

We use the basic kinematics equation,

`v=u+at`

• `u` is the initial velocity of the object

• `a` is the acceleration of the object

• `t` is the time taken

Rearranging for `a`, we get:

`a=(v-u)/t`

• `v` is the final velocity of the object

And so,

`a=(60 \ "m/s"-25 \ "m/s")/(5 \ "s")`

`=(35 \ "m/s")/(5 \ "s")`

`=7 \ "m/s"^2`