A stone is dropped from top of a cliff.It is seen to hit the ground below after 4.2 s. How high is the cliff?

Explanation

To find the height of the cliff from which a stone is dropped, we can use the kinematic equation for uniformly accelerated motion. Here’s a step-by-step solution:

### Step 1: Identify the known values
- The time \( t \) taken for the stone to hit the ground is \( 4.2 \) seconds.
- The initial velocity \( u \) of the stone is \( 0 \) m/s (since it is dropped).
- The acceleration \( a \) is due to gravity, which is approximately \( 9.8 \) m/s².

### Step 2: Use the kinematic equation
...