Question

A block is sliding down on an inclined plane. The velocity changes at a constant rate from $10cm{s}^{-1}$ to $15cm{s}^{-1}$ in 2 seconds. What is its acceleration?

• A. $2.5cm{s}^{-2}$
• B. $1.5cm{s}^{-2}$
• C. $4.5cm{s}^{-2}$
• D. $1.25cm{s}^{-2}$

Answer 1

The correct option is A

$2.5cm{s}^{-2}$

The motion is depicted below

Here,
final velocity v = $15cm{s}^{-1}$, initial velocity u = $10cm{s}^{-1}$ and time taken t = 2 s
Let 'a' be the acceleration.

From 1st equation of motion,
$a=\frac{v-u}{t}$
$a=\frac{15-10}{2}$
$\Rightarrow$$\text{acceleration}=2.5cm{s}^{-2}$