A body of mass `1 kg` is thrown upwards with a velocity `20 ms^(-1)`. It momentarily comes to rest after attaining a height of `18 m`. How much energy is lost due to air friction? `(g = 10 ms^(-2))`

Options

A. `20 J`
B. `30 J`
C. `40 J`
D. `10 J`

Explanation

To find the energy lost due to air friction when a body of mass `1 kg` is thrown upwards with an initial velocity of `20 m/s` and reaches a height of `18 m`, we can follow these steps:

### Step 1: Calculate the initial kinetic energy (KE_initial)
The initial kinetic energy can be calculated using the formula:
\[ KE_{\text{initial}} = \frac{1}{2} m v^2 \]
Where:
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