功函數(shù)的測量

功函數(shù)的測量數(shù)據(jù)處理數(shù)據(jù)表格T/K12345671726Ve(1)6.186.336.466.606.736.856.98Vdiv36.0049.0264.0181.01100.01121.00144.006.007.008.009.0010.0011.0012.00logVe0.790990.801400.810230.819540.828020.835690.843861795Ve(1)20.4320.9421.4621.9122.3822.9323.38Vdiv36.0049.0064.0081.02100.02121.01144.026.007.008.009.0010.0011.00012.000logVe1.310271.320981.331631.340641.349861.360401.368841862Ve(1)64.4265.8767.4668.8970.2471.6473.02Vdiv36.0049.0264.0081.02100.03121.01144.026.007.008.009.0010.0011.0012.00logVe1.809021.818691.829051.838161.846581.855161.863441929Ve(10)17.7918.1818.6018.9819.3219.8020.13Vdiv36.0049.0200064.0081.00100.00121.00144.016.007.008.009.0010.0011.0012.00logVe1.250181.259591.269511.278301.286011.296671.303841995Ve(10)45.6146.5347.4078.2049.0549.8250.66Vdiv36.0449.0164.0381.03100.03121.01144.026.007.008.009.0010.0011.0012.00logVe1.659061.667731.675781.893211.690641.697401.704672058Ve(10)103.68105.97108.38110.68112.78114.87116.67Vdiv36.0149.0264.0881.06100.06120.98144.026.007.008.009.0010.0011.0012.00logVe2.015692.025182.034952.044072.052232.060212.06696進(jìn)行第一輪擬合：在擬合中要注意，在使用10檔測量的Ve要乘以10（或logVe+1）后再擬合，結(jié)果如下：第一輪擬合結(jié)果T/K1/T/1/K截距Ve/mv17265.7937410-040.739785.4926717955.5710310-041.2526917.8934618625.3705710-041.7556056.9635019295.1840310-042.19684157.3391019955.0125310-042.64477441.3368620584.8590910-042.96521923.02807進(jìn)行第二輪擬合：1/T/1/K截距5.7937410-040.739785.5710310-041.252695.3705710-041.755605.1840310-042.196845.0125310-042.644774.8590910-042.96521斜率k：-22006.63331Φ=k/-50394.367eV關(guān)于Ie的計(jì)算必要性的討論在理論公式=1\*GB3…①…=2\*GB3②中，若將Ie換成Ue，由Ie=Ue/Re得：在=2\*GB3②中在①中由此可見，是否計(jì)算Ie，對最后求斜率并沒有影響，所以在處理數(shù)據(jù)時(shí)，沒有必要計(jì)算Ie，而是直接進(jìn)行擬合。思考題：燈絲KH兩端有電壓降，怎樣才能直接測出燈絲KH中點(diǎn)和板極A1之間的電壓Ua？答：將兩個(gè)18KΩ的電阻R串聯(lián)后并聯(lián)在燈絲兩端，然后將電壓源正級接在A1，將電壓源的負(fù)極接在兩電阻的中點(diǎn)，這樣相當(dāng)于在燈絲的中點(diǎn)接上了電壓源的負(fù)極，從而直接測出燈絲KH中點(diǎn)和板極A1之間的電壓Ua將兩個(gè)18KΩ的電阻R串聯(lián)后并聯(lián)在燈絲兩端起什么作用？它們對于測量燈絲的電流有何影響？答：作用在第一題中有答案，它們對于測量燈絲的電流有限流的作用。保護(hù)級A2的作用是什么？它應(yīng)怎樣接入電路中？答：保護(hù)環(huán)的電位與陽極相近，使陽極電流就不受邊緣電場不均勻的影響了，他的另一個(gè)作用是保證了所使用的燈絲中段的溫度是均勻的，避免了燈絲兩頭“冷端”的影響。實(shí)驗(yàn)中