Figure 14 shows a spring standing on a table - Edexcel - GCSE Physics - Question 6 - 2020 - Paper 1

To estimate the original length of the spring, follow these steps:

1. Place the spring upright on a flat surface, ensuring it is not compressed.
2. Use a ruler with millimeter divisions to measure the length of the spring from the bottom to the top coil.
3. Ensure that your eye is level with the measurement point to prevent parallax error.
4. Record the measurement for accuracy.

1. Use a ruler with a finer measurement division to enhance accuracy in length readings.
2. Take multiple readings and average them to minimize the effect of random errors in measurement.

The reduction in length reaches a limit because the coils of the spring are pushed together and eventually touch, meaning no further extension can occur regardless of additional weight.

To find the spring constant k, use Hooke's law, which is expressed as: $k = \frac{F}{x}$ Where:

• F = 0.5 N (force applied)
• x = 13 mm = 0.013 m (extension in meters)

Substituting the values: $k = \frac{0.5}{0.013} = 38.46 \text{ N/m}$ Thus, the spring constant k is approximately 38.5 N/m.

To calculate the extension of the spring, we can use the work-energy principle: $E = \frac{1}{2} k x^2$ Where:

• E = 0.14 J (work done)
• k = 175 N/m (spring constant)

Rearrange the equation for x: $x^2 = \frac{2E}{k}$ Then, $x^2 = \frac{2 \times 0.14}{175}$ Calculating yields: $x^2 = 0.0016$ Thus, x = √(0.0016) = 0.04 m. Therefore, the extension of the spring is 0.04 m.