1. The maximum error of the atomic casesium clock installed at hte Hong
Kong Observatory is 10^-6 s per day.
a) What is the its possible percentage error? 1.16x10^-9 %
b) How long would it take to be in error by 1s? 1000000days
2. Mary uses a stop-watch to measure a period of time and the overall error
due toher reaction time in starting and stopping a stop-watch is 0.4s. If
the maximum percentage error is 1%, what is the minimum period? 40s
3. Liu Xiang won the 110-m hundles in the 2004 Olympic Games. His
result was 12.91 s.
a) The overall timing error due to the reation time of an average person is
about 0.3s. What is the percentage error in timing an event of about
10s by a stop-watch? 3%
b) Explain why stop-watches are not used to measure time intervals of
110-m hurdles in the Olympc Games.
4. John's watch runs slower than the actual time by one minute each time b one minute each day. John adjusted the watch to correct time at 2:00 pm on 1 January 2009.
a) What time should be shown on John's watch when the actual time is
2:00 pm on 10 Januar 2009? Explain your answer briefly.
1:51 pm on 1 January 2009
b) What is the percentage error of time shown on John's watch as
compared with the correct time? 6.94x10^-2%
How can i get the answer? Thanks!1
Physics Questions
2010-03-01 8:06 am
回答 (1)
2010-03-03 6:18 pm
✔ 最佳答案
1.a. Possible percentage error = (10^-6)/(24 X 60 X 60) X 100% = 1.16 X 10^-9 %b. To attain this error, time required = 1 / (1.16 x 10^-9%) = 8.64 X 10^10 s = 1 000 000 days
2. Minimum period = Maximum error / Percentage error = 0.4 / 1% = 40 s
3.a. Percentage error = Maximum error / Period = 0.3 / 10 = 3%
b.
This will lead to a large error, especially in the hundred hurdle
event, such large error can determine the position of the competitors.
4.a. For 10 Jan 2009, ten days have passed. So, the watch should be slower than the actual time by 1 X 10 = 10 mins
So, the shown time = 1:51 pm on 10 Jan 2009.
b. Percentage error = Maximum error / Period = 10 / (60 X 24 X 10) X 100% = 6.94 X 10^-2 %
參考: Physics king
收錄日期: 2021-04-19 21:29:03
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