Bell in Bell Jar Manufacturer,Supplier and Exporter in India
Product Code : EL-SLE-4794
Jlab Export is a leading Bell in Bell Jar Manufacturer,and suppliers in India
Bell in Bell Jar (code EL-SLE-4794) is a sound demonstration apparatus: an electric bell hung inside a bell jar on a plate with a vacuum pump plate, used to show that sound needs a material medium to travel. The bell works on 4–6 V AC/DC and hangs from a rubber cord, with coiled wire leads to terminals on the rubber bung that seals the jar. It is made by Jain Laboratory Instruments Pvt Ltd (JLab) at its works in Ambala, India.
Specifications
| Parameter | Detail |
|---|---|
| Assembly | Bell jar with plate and vacuum pump plate |
| Bell | Standard electric bell, 4–6 V AC/DC |
| Bell mounting | Held by a rubber cord inside the bell jar |
| Connections | Coiled wire leads to terminals fitted in a rubber bung that seals the jar |
| Demonstrates | Sound needs a material medium to propagate |
| Jar size and vacuum pump | Jar dimensions are not stated; a vacuum pump is not listed as included |
| Quality check | Each set is visually inspected before dispatch |
| Pack quantity | Each (sold individually) |
| Minimum order quantity | 10 units |
| Dispatch time | Usually 7–10 working days |
| Product code | EL-SLE-4794 |
| Manufacturer | Jain Laboratory Instruments Pvt Ltd (JLab) — OEM |
| Country of origin | India (made in Ambala, Haryana) |
How Does It Compare with the Bell and Vacuum Sound Jar?
| Model | Bell power | Listed contents |
|---|---|---|
| This apparatus (EL-SLE-4794) | Electric bell on 4–6 V AC/DC through terminals in the bung | Bell jar, plate, vacuum pump plate, bell on rubber cord |
| Bell and Vacuum Sound Jar Glass | Battery bell inside the jar; no external power source needed (batteries not included) | Bell jar, bell, vacuum pump plate and vacuum hose |
Choose this apparatus when you want to run the bell from a low-voltage lab supply through sealed terminals. The battery version avoids external wiring and also lists a vacuum hose.
What Is the Bell in Bell Jar Used For?
It is the classic experiment for the class 9 science chapter on sound and for introductory college physics. The bell is switched on inside the sealed jar and students hear it ring. As a vacuum pump draws the air out through the pump plate, the ringing becomes fainter and fainter, although the hammer can still be seen striking the gong; when air is let back in, the sound returns. The result shows that sound is carried by a material medium such as air, while light, which still lets students see the bell, can cross the near-vacuum. Hanging the bell on a rubber cord reduces the sound carried through its support, so the faint sound that remains comes mainly through the air left in the jar.
Smear a little vacuum grease on the rim of the jar before pumping so that the seal holds. An evacuated glass jar is under strong outside pressure, so keep it clear of knocks, use a safety screen for class demonstrations, and let air back in slowly. Power the bell from cells or a low-voltage supply only.
What to Specify When Ordering
- Quantity — the minimum order is 10 sets; schools often buy one per lab for teacher demonstrations.
- Vacuum pump — a pump is not part of this listing; add a hand or rotary vacuum pump if your lab has none.
- Power supply — the bell needs 4–6 V AC/DC; add a low-voltage supply or cells if required.
- Spares — mention spare bells or bungs if you want them quoted.
Frequently Asked Questions
What does the bell in bell jar experiment show?
That sound needs a material medium to travel. As air is pumped out of the jar the ringing fades, even though the bell is still working, and it returns when air is let back in.
What voltage does the bell need?
4–6 V, AC or DC, connected through the terminals on the rubber bung. Do not connect it to mains electricity.
Is a vacuum pump included?
No pump is listed. The apparatus has a vacuum pump plate for connecting one; JLab lists hand and rotary vacuum pumps separately.
Why is the bell hung from a rubber cord?
So that little sound travels from the bell through its support into the jar walls. That keeps the drop in loudness clear as the air is removed.
How is it different from the Bell and Vacuum Sound Jar?
This set runs its electric bell from an external 4–6 V supply through sealed terminals. The other listing has a battery bell inside the jar and includes a vacuum hose.
What should I send for an export quotation?
The quantity, the destination country and port or city, preferred delivery terms such as FOB or CIF, packing or labelling requirements, and any tender reference.
Who manufactures the Bell in Bell Jar?
JLab (Jain Laboratory Instruments Pvt Ltd) makes it at its works in Ambala, Haryana, India.
OEM Manufacturer
JLab is the trading name of Jain Laboratory Instruments Pvt Ltd, a manufacturer of physics lab equipment for schools and colleges in India, incorporated in 2017 and based on Hargolal Road, Ambala, Haryana. The bell-in-bell-jar set is made at JLab’s own works rather than bought from a trader, so schools, colleges, dealers and importers buy factory-direct, each set is inspected visually before dispatch, and repeat orders are handled by the manufacturer. JLab exports worldwide and ships to buyers in every region — for example the Netherlands in Western Europe, DR Congo in Central Africa, Eswatini in Southern Africa, Zambia in East Africa and Turkmenistan in Central Asia. Tender details are on the JLab lab tenders page.
Vacuum and Sound Apparatus
- Hand Vacuum Pump — a lightweight hand-operated pump for evacuating the jar.
- Vacuum Pump — an electric rotary vane vacuum pump.
- Bell and Vacuum Sound Jar Glass — the battery-bell version with vacuum hose.
- Bell Jar — a borosilicate glass bell jar with socket top.
- Electric Bell Buzzer — a miniature 4–6 V AC/DC bell buzzer.
- Resonance Box with Tuning Fork — for further sound and resonance demonstrations.
More apparatus is in the School Lab Equipment range.
Request a Quote
JLab quotes directly as the manufacturer. Use the Add To Cart enquiry button on this page or the contact page to send the number of sets (minimum 10 units), whether you need a vacuum pump or power supply with them, and your delivery location.
Last updated: 4 October 2026
