Ball and Ring Apparatus
Product Code : EL-H-10395
Quick answer: The Ball and Ring Apparatus is a classic heat demonstration of the thermal expansion of solids: the 19 mm brass ball slips through the brass ring when cold but sticks once heated. The ball is held on a chain and both parts have wooden handles. Lab Exports manufactures it in Delhi for schools and colleges.
Specifications
| Item | Specification |
|---|---|
| Ball | Brass, 19 mm diameter, captive on a chain |
| Ring | Brass, mounted on a rod with wooden handle |
| Handles | Wooden (insulated), on ball and ring |
| Principle demonstrated | Thermal expansion of solids |
| Category | Physics Lab - Heat |
How the ball and ring experiment is done
The ball and ring experiment, also known as 's Gravesande's ring, shows that a solid grows in every direction when it is heated. At room temperature the brass ball is just small enough to pass through the brass ring. After heating, its diameter increases slightly - by about alpha x d x delta T, where alpha for brass is roughly 19 x 10^-6 per deg C - and it no longer fits.
- Pass the cold ball through the ring to show that it fits.
- Hold the ball by its wooden handle in a Bunsen or spirit flame for a few minutes.
- Try to pass the hot ball through the ring; it now rests on top.
- Leave the ball resting on the ring: as the ball cools and the ring warms, the ball drops through.
The same principle explains the gaps left in railway tracks, expansion joints in bridges and why a tight metal lid loosens under hot water, which makes the demonstration a useful lead-in to linear and volume expansion.
Key features
- Brass ball of 19 mm diameter matched to a brass ring
- Ball held captive on a chain so the hot ball cannot be dropped or misplaced
- Wooden handles on both parts for handling when hot
- Clear yes/no visual result that a whole class can see
- Simple, robust construction for repeated heat demonstrations
Documentation and supply
Most Lab Exports products carry a one-year manufacturer warranty.
Lab Exports manufactures the Ball and Ring Apparatus at its works in Laxmi Nagar, Delhi, and supplies it to schools and colleges in India and 60+ countries, handling the export documents for each shipment. More about the company is on the About Lab Exports page.
Related Heat products
- Bar and Gauze Apparatus Aluminium (EL-H-10396)
- Pyrometer (EL-H-10397)
- Linear Expansion Apparatus (EL-H-10398)
- Searle's Thermal Conductivity Apparatus (EL-H-10399)
- Lee's and Charlton's Apparatus (EL-H-10400)
- Joule's Calorimeter (EL-H-10401)
The full range is in the Heat section of the Physics Lab range.
Frequently asked questions
What does the ball and ring apparatus demonstrate?
The thermal expansion of solids. The brass ball passes through the ring when cold but will not pass through after it has been heated, because its diameter has increased.
What size is the ball?
The ball is brass, 19 mm in diameter, and is attached to the apparatus by a chain.
Why does the heated ball eventually pass through the ring?
As it rests on the ring it loses heat and contracts while the ring warms and expands slightly, so the two sizes come back into line and the ball drops through.
What is the price of the Ball and Ring Apparatus?
Prices are not published on the website. Add the Ball and Ring Apparatus to the Enquiry Cart with the Add To Cart button on this page, or email [email protected] with the house code EL-H-10395 and the quantity, to receive a quotation.
Does Lab Exports manufacture the Ball and Ring Apparatus?
Yes. Lab Exports manufactures the Ball and Ring Apparatus at its works at 11/315, Lalita Park, Laxmi Nagar, Delhi 110092, under house code EL-H-10395.
Request a quote
Email [email protected] with the house code EL-H-10395 and the quantity, or add the Ball and Ring Apparatus to the Enquiry Cart with the Add To Cart button on this page. Tender buyers can also see the Tenders and OEM page.
