Figure 11 shows a stationary apple hanging from a tree - AQA - GCSE Physics Combined Science - Question 7 - 2022 - Paper 2

To calculate the distance fallen, we can use the formula: $s = ut + \frac{1}{2}at^2$ Where:

• $s$ = distance fallen
• $u$ = initial velocity = 0 m/s
• $a$ = acceleration due to gravity = 9.8 m/s²
• $t$ = time = 0.5 s

Substituting the values: $s = 0 \times 0.5 + \frac{1}{2} \times 9.8 \times (0.5)^2$
$s = 0 + \frac{1}{2} \times 9.8 \times 0.25$
$s = 0 + 1.225 = 1.225 m$
Therefore, the distance fallen by the apple is approximately 1.2 m.

The assumption that acceleration is constant at 9.8 m/s² assumes:

1. No air resistance affects the apple as it falls.
2. The effects of any changes in mass or drag forces are negligible.

However, in reality:

• As the apple falls, air resistance increases which results in a decrease in the resultant force acting on the apple.
• Hence, the acceleration is not entirely constant as it may reduce due to increasing air resistance.

It's reasonable to assume constant acceleration for small distances or short time frames, but for larger falls, this assumption becomes less accurate.