A stone was dropped from the top of a tall cliff - Junior Cycle Science - Question (c) - 2009

To estimate the acceleration, we can use the slope of the velocity-time graph. From the graph:

• At 0 seconds, the velocity is 0 m/s.
• At 5 seconds, the estimated velocity is 50 m/s.

The change in velocity ( Δv) is 50 m/s - 0 m/s = 50 m/s and the change in time ( Δt) is 5 s - 0 s = 5 s.

Using the formula for acceleration: $a = \frac{\Delta v}{\Delta t} = \frac{50 \, \text{m/s}}{5 \, \text{s}} = 10 \, \text{m/s}^2$

Thus, the acceleration of the stone is 10 m/s².

The force that caused the stone to fall is gravity.

The weight of the stone can be calculated using the formula: $\text{Weight} = \text{mass} \times g$ where $g \approx 9.8 \, \text{m/s}^2$. Thus, $\text{Weight} = 2 \, \text{kg} \times 9.8 \, \text{m/s}^2 = 19.6 \, \text{N}$

The unit of weight is Newton (N).