e/M lab

--Michael T. Lancaster 17:18, 22 October 2007 (CDT)

Current (A) held constant	--Voltage (V)--	r (cm) (left side)--	r (cm) (right side)--	r (cm) average
1.52	296	5.5	6.5	6
	311	5.5	7.1	6.3
	325	6.0	6.3	6.15
	340	6.0	7.3	6.65
	355	6.2	7.0	6.6
	370	5.8	7.2	6.5
	385	6.2	7.4	6.8
	400	6.3	7.5	6.9
	416	6.5	7.5	7
	430	6.5	7.5	7
	445	6.5	7.5	7
	454	6.5	7.8	7.15

constant voltage	Current (ampheres)	r (right side) (cm)	r (left side) (cm)	r average (cm)
454 V	2.25	7	6	6.5
	2.1	5.5	5	5.25
	1.95	6.5	5.3	5.9
	1.79	6.5	6	6.25
	1.65	6.75	6	6.37
	1.50	7	6.5	6.75
	1.35	7.5	7	7.25
	1.2	7.5	7.75	7.675

--Michael T. Lancaster 12:19, 19 November 2007 (CST)

Initial theory

F=qvB

ma = mv^2/r

qvB = mv^2/r

qB = mv/r

q/m = v/(rB)

Since both q (=e) and m (=mass of the electron) are constant then v/(rB) should be constant.