0-5V DC Moving Coil Voltmeter Category_Demonstrations One-inch brass ball that threads

One-inch brass ball that threads onto a pendulum string as a heavier metal counterpart to aluminum or steel balls in mass-dependent periodic-motion investigations

and single-celled organism structure for protist biology teaching

copper-coated

Five-centimeter brass sphere mounted on an ebonite-insulated metal base

providing the more readily oxidized electrode that drives current in classic galvanic-cell demonstrations

0-5V DC Moving Coil Voltmeter Category_Demonstrations One-inch brass ball that threadsFive volt moving coil DC voltmeter at plus or minus 2. 5% accuracy in a fully enclosed plastic case, sized to read single cell and small battery pack voltages without scale overshoot risk.