• Submitted By: gwc0912
• Date Submitted: 12/21/2013 2:59 AM
• Category: Technology
• Words: 1352
• Page: 6
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Experiment report

Subject: physics
Group No.: 1-2A
Student No.: SH-10-0730G
Student Chinese Name: 顾未辰
Student Name (Pinyin): Gu Weichen
Student English Name: Bill
Teacher Name: Channa Phillip
Date: 2011-3-18

Title | Introduction | Apparatus and Method | Measurements | Processing | Discussion |
| | | | | |
Conclusion | References | English | Total | Comments |
| | | | |
Experiment report

NAME: Bill
PIN YIN: Gu Weichen
PERSON ID: SH-10-0730G
CLASS NUMBER: ENG 1-2A

Introduction
Aim:
1. Simulate radioactive decay in the Excel to get the decay constant.
2. Find the λ which is the radioactive decay constant.
3. Analyze the error between the theoretical value of decay constant and experimental value of decay constant.

Material:
Laptop, Microsoft Office Excel

Theory:
Half-life is the period of time, for a substance undergoing decay, to decrease by half.
A=-dNdt
-dNdt=λN
NN-dNN=-0tλ*dt
lnN-lnN0=-λt
lnNN0=-λt
e-λt=NN0
Nt=N0e-λt
N02=N0e-λt1/2
12=eλt1/2
ln2=λt1/2
λ=ln2t1/2

Where A is activity; N0 is the initial quantity of the nuclei; Nt is the quantity that the nuclei still remains and has not decayed after the time t; λ is the decay constant; t1/2 is the half-life of the nuclei.

History:
Radioactivity was found by Becquerel in 1896 who won the Nobel Prize. He noticed the radioactivity by accident that uranium salt crystals can release a radiation to the photographic plate even it is covered in the box. Finally he found out the radioactivity.

Method
Steps:
1. Choose an element as the investigate substance from the Periodic Table and find the half-life. For example, silver (Ag108) and half-life of 418 years.
2. Open radioactive decay simulation program in the Excel and put the half-life into the Excel and get the decay constant.
3. Choose three different initial numbers of nuclei which range from 1~20, 100~1000 and...