Weight Bars for Hook’s Law Apparatus

In Hooke’s Law experiments, the weight bars or hanger is used to apply a measurable force (often by hanging masses) to a spring or elastic material to observe its extension. The setup helps verify Hooke’s Law, which states that the force $F$ applied to a spring is directly proportional to the extension $x$ it causes, provided the elastic limit is not exceeded:

F=kx

Where:

• F is the applied force (often the weight in Newtons),
• x is the extension of the spring,
• k is the spring constant (a property of the spring).

Key Components of a Hooke’s Law Apparatus Weight Bar:

1. Weight Hanger:
   • A bar or rod designed to hold weights securely.
   • Often made of metal, lightweight, with hooks or clips to attach to the spring.
   • It typically weighs a small, known amount (e.g., 50 g or 100 g), which is included in the total weight applied to the spring.
2. Slotted Weights:
   • Weights with holes or slots can easily be added or removed from the weight hanger.
   • Common increments: 50 g, 100 g, 200 g, etc.
   • It is made of metal, with accurate labeling for precise measurements.
3. Material:
   • The weight bar and weights are usually made of brass, steel, or aluminum for durability and precision.
4. Precision:
   • For experiments, precision is critical, so the weights should be standardized and calibrated.

Usage:

• The weight hanger is attached to the bottom of the spring.
• Weights are incrementally added to the bar, measuring the extension of the spring after each addition.
• The force applied by the weights is calculated by multiplying the mass of the weights by gravity ($F=mg$), where g≈9.8 m/s2g \approx 9.8 \, m/s^2g≈9.8m/s2.