Instrument Accuracy

**Table 1:** Instrument Accuracy - Mechanics
Dimension	Instrument	Instrument Precision	Instrument Accuracy (max. relative error)	Common Error Limiting Factor
Length	meter stickCenco 73115^†	0.5 mm	< 0.5%	visual
Length	Vernier calipersCraftsman 40257^†	0.05 mm	0.1%	misreading scale
Mass	electronic balanceOhaus GT 4000^†	0.1 g	0.1% to 1%	calibration
Time	digital stopwatchPASCO SE-8755^†	0.01 s	~0.001%	reaction time (~0.2 s)
Time	photogatePASCO ME-9206A^†	5 ms	0.50%	data processing
Time	Smart TimerPASCO ME-8930^†	0.1 ms	0.01% of full scale	calibration
Frequency	signal generatorInstek FG-8016G^†	0.1 Hz	1%	calibration
Freefall Time	Tape TimerPASCO ME-9283^†		0.1%	obstruction
Time/dist	Spark generatorDaedalon EA-50^†		0.1%	wrinkled paper, spin on inelastic
Angle	Digital LevelSpi-Tronic Pro 3600^†	0.05°	0.05°	unstable level

**Table 2:** Instrument Accuracy - Electricity and Magnetism
Dimension	Instrument	Instrument Precision	Instrument Accuracy (max. relative error)	Common Error Limiting Factor
V, I, R	multimeterRadio Shack 22-163, Micronta 22-167^†	4.5 digits	DCV: 1% ACV: 1.5% DCA (< 30 mA): 1% DCA (0.3 to 10 A): 2% R (< 300 kΩ): 1% R (0.3 to 3 MΩ): 2%	extra resistance, calibration
V, I, R	multimeterFluke 77 Series II^†	4.5 digits	0.3% for 1 mV to 320 V 1.5% for 0.1 mA to 10 A 0.5% for 1Ω to 3.2 MΩ	calibration
V, I, R	multimeterKeithley 178 DMM^†		(see bottom of meter)	extra resistance, calibration
Capacitance	capacitance meterBK 810B^†	3.5 digits	0.5% for 200 pF to 0.2 mF 2% for 0.2 mF to 20 mF	calibration, stray capac.
Inductance	LCR meterBK 875 A^†	3.5 digits	3% for C < 0.2 mF 3% for L < 20 H	calibration
V, freq.	oscilloscopeTektronix 2211, 2213^†	2 digits	3% for both gain and sweep	visual resol., calibration
Resistance	Decade resistorGeneral Radio Co. 1432-N, 1432-A, 1432-J^†		10%	calibration
Resistance	Resistance subst. boxHeath EUW-28^†	7 Ohms	10%	calibration
Inductance	Decade inductorWide Range Electronics ALD-12^†	1 mH	10%	calibration
Mag. Field	Hall ProbeFW Bell 5070^†	0.01 mT	±2% DC, ±3.5% AC	probe alignment