Decade Capacitance Box, Model F Graduations_Ungraduated each foam-protected in a wooden

each foam-protected in a wooden case with frequencies labeled

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 continuous DC demonstrations beyond the reach of dry-cell stacks

supplied in a storage case for student precision work

Compass mounted parallel to a current-carrying coil deflects against Earth's horizontal field

Decade Capacitance Box, Model F Graduations_Ungraduated each foam-protected in a woodenUsed to substitute calibrated capacitance into AC circuits without rewiring, this decade box selects cascaded values for RC time constant, resonance, and frequency response student work.