17.3. Millikan Oil Drop Experiment http://www.ck12.org
Practice
Questions
The following video covers Millikan’s oil drop experiment. Use this resource to answer the following questions.
http://www.youtube.com/watch?v=XMfYHag7Liw&noredirect=1
MEDIA
Click image to the left for use the URL below.
URL: http://www.ck12.org/flx/render/embeddedobject/64694- What was the purpose of the x-rays passing through the instrument?
- At which university was Millikan’s oil drop experiment conducted?
Review
Questions
- Give reasons for each drop requiring a different voltage to balance.
- Why do some oil drops not react to adjustments in voltage?
- Why do some drops fall faster instead of slower when you increase the voltage?
- In another universe, where the unit for charge is the mork, a physicist performed the Millikan oil drop
experiment and measured the following charges on a series of oil drops.
TABLE17.1:
Trial Charge Trial Charge
1 2. 62 × 10 −^13 mork 4 5. 14 × 10 −^13 mork
2 3. 93 × 10 −^13 mork 5 6. 55 × 10 −^13 mork
3 1. 31 × 10 −^13 mork- Which of the following is the best choice for the charge on an electron in morks?
(a) 2. 62 × 10 −^13 mork
(b) 6. 55 × 10 −^13 mork
(c) 1. 31 × 10 −^13 mork
(d) 1. 6 × 10 −^13 mork
(e) None of these. - An oil drop weighs 1. 9 × 10 −^15 Nand it suspended in an electric field of 6. 0 × 103 N/C.
a. a. What is the charge on the drop?
b. How many excess electrons does it carry?- Millikan oil drop experiment:The purpose of Robert Millikan’s oil-drop experiment (1909) was to measure
the electric charge of the electron. He did this by carefully balancing the gravitational and electric forces on
tiny charged droplets of oil suspended between parallel charged metal plates.