Logarithm Table

When using the component of the capacitor and so on with the electronic circuits,
the logarithm must be computed to look for the electric current which flows through the circuit.
The logarithm computation can be computed with the function computer but I show the tables of logarithm in this page.

The formula is shown below and it looks for the X.
e is the base of the natural logarithm and the value is 2.71828.

n = e^x

It becomes the following when changing into the formula which looks for the X.

x = log_en

So as not to confuse with the common logarithm("log₁₀" or it is simply expressed with "log"),
"log_e" is sometimes expressed with the "ln".
x = ln n
In case of n=1, it becomes x=0 and when the n is less than 1, x becomes the negative value.
When the n is less than 1, it becomes the same as the one to have made x which is due to the value of 1/n negative.

The natural logarithm table (Equal to or less than 1.0)

n	log_en	n	log_en	n	log_en	n	log_en
0.01	-4.60517	0.26	-1.34707	0.51	-0.67334	0.76	-0.27443
0.02	-3.91202	0.27	-1.30933	0.52	-0.65392	0.77	-0.26136
0.03	-3.50655	0.28	-1.27296	0.53	-0.63488	0.78	-0.24846
0.04	-3.21887	0.29	-1.23788	0.54	-0.61618	0.79	-0.23572
0.05	-2.99573	0.30	-1.20397	0.55	-0.59783	0.80	-0.22314
0.06	-2.81341	0.31	-1.17118	0.56	-0.57982	0.81	-0.21072
0.07	-2.65926	0.32	-1.13943	0.57	-0.56212	0.82	-0.19845
0.08	-2.52573	0.33	-1.10866	0.58	-0.54472	0.83	-0.18633
0.09	-2.40794	0.34	-1.07881	0.59	-0.52763	0.84	-0.17435
0.10	-2.30258	0.35	-1.04982	0.60	-0.51082	0.85	-0.16252
0.11	-2.20727	0.36	-1.02165	0.61	-0.49430	0.86	-0.15082
0.12	-2.12026	0.37	-0.99425	0.62	-0.47803	0.87	-0.13926
0.13	-2.04022	0.38	-0.96758	0.63	-0.46203	0.88	-0.12783
0.14	-1.96611	0.39	-0.94161	0.64	-0.44629	0.89	-0.11653
0.15	-1.89712	0.40	-0.91629	0.65	-0.43078	0.90	-0.10536
0.16	-1.83258	0.41	-0.89160	0.66	-0.41551	0.91	-0.09431
0.17	-1.77196	0.42	-0.86750	0.67	-0.40047	0.92	-0.08338
0.18	-1.71480	0.43	-0.81419	0.68	-0.38566	0.93	-0.07257
0.19	-1.66073	0.44	-0.82098	0.69	-0.37106	0.94	-0.06187
0.20	-1.60944	0.45	-0.79851	0.70	-0.35667	0.95	-0.05129
0.21	-1.56065	0.46	-0.77653	0.71	-0.34249	0.96	-0.04082
0.22	-1.51412	0.47	-0.75502	0.72	-0.32850	0.97	-0.03046
0.23	-1.46968	0.48	-0.73397	0.73	-0.31471	0.98	-0.02020
0.24	-1.42711	0.49	-0.71335	0.74	-0.30110	0.99	-0.01005
0.25	-1.38629	0.50	-0.69214	0.75	-0.28768	1.00	-0.00000

The natural logarithm table (Equal to or more than 1.0)

n	log_en	n	log_en	n	log_en	n	log_en
1.0	0.00000	3.0	1.09861	5.0	1.60944	25.0	3.21887
1.1	0.09531	3.1	1.13140	6.0	1.79176	26.0	3.25809
1.2	0.18232	3.2	1.16315	7.0	1.94591	27.0	3.29583
1.3	0.26236	3.3	1.19392	8.0	2.07944	28.0	3.33220
1.4	0.33647	3.4	1.22377	9.0	2.19722	29.0	3.36729
1.5	0.40546	3.5	1.25276	10.0	2.30258	30.0	3.40119
1.6	0.47000	3.6	1.28093	11.0	2.39789	40.0	3.68888
1.7	0.53063	3.7	1.30833	12.0	2.48491	50.0	3.91202
1.8	0.58779	3.8	1.33500	13.0	2.56495	60.0	4.09434
1.9	0.64185	3.9	1.36097	14.0	2.63905	70.0	4.24849
2.0	0.69314	4.0	1.38629	15.0	2.70805	80.0	4.38202
2.1	0.74193	4.1	1.41099	16.0	2.77259	90.0	4.49981
2.2	0.78845	4.2	1.43508	17.0	2.83321	100.0	4.60517
2.3	0.83291	4.3	1.45861	18.0	2.89037	200.0	5.29832
2.4	0.87547	4.4	1.48160	19.0	2.94444	300.0	5.70378
2.5	0.91629	4.5	1.50408	20.0	2.99573	400.0	5.99146
2.6	0.95551	4.6	1.52605	21,0	3.04452	500.0	6.21461
2.7	0.99325	4.7	1.54756	22,0	3.09104	600.0	6.39693
2.8	1.02962	4.8	1.56861	23.0	3.13549	700.0	6.55108
2.9	1.06471	4.9	1.58923	24.0	3.17805	800.0	6.68461

At the electronic circuits, the common logarithm(the logarithm having base 10) is used for the thing except above-mentioned natural logarithm.

n = 10^x

x = log₁₀n

This value is used when it expresses the mu factor and so on and compares the two values.
The common logarithm is used for the dB ( decibel ).
The noise to the electric signal sometimes show the 1/1000 or 1/10000 values and so on.
It shows in the dB because the number of the figures increases when displaying just as it is.

In case of the voltage ratio : dB = 20 log₁₀ (V1/V2)

In case of the electric power ratio : dB = 10 log₁₀ (P1/P2)

It represents as -60 dB in case of V1=0.001 V , V2=1 V.

When the voltage ratio is twice, it is 6 dB.
When the electric power ratio is twice, it is 3 dB.

The common logarithm table

n	log₁₀n	n	log₁₀n	n	log₁₀n	n	log₁₀n
0.0001	-4.00000	1.0	0.00000	3.0	0.47712	5.0	0.69897
0.001	-3.00000	1.1	0.04139	3.1	0.49136	5.1	0.70757
0.01	-2.00000	1.2	0.07918	3.2	0.50515	5.2	0.71600
0.02	-1.69897	1.3	0.11394	3.3	0.51851	5.3	0.72427
0.03	-1.52287	1.4	0.14612	3.4	0.53148	5.4	0.73239
0.04	-1.39794	1.5	0.17609	3.5	0.54406	5.5	0.74036
0.05	-1.30103	1.6	0.20412	3.6	0.55630	5.6	0.74819
0.06	-1.22184	1.7	0.23045	3.7	0.56820	5.7	0.75587
0.07	-1.15490	1.8	0.25527	3.8	0.57978	5.8	0.76342
0.08	-1.09691	1.9	0.27875	3.9	0.59106	5.9	0.77085
0.09	-1.04575	2.0	0.30103	4.0	0.60206	6.0	0.77815
0.1	-1.00000	2.1	0.32222	4.1	0.61278	6.1	0.78533
0.2	-0.69897	2.2	0.34242	4.2	0.62325	6.2	0.79239
0.3	-0.52288	2.3	0.36172	4.3	0.63347	6.3	0.79934
0.4	-0.39794	2.4	0.38021	4.4	0.64345	6.4	0.80618
0.5	-0.30103	2.5	0.39794	4.5	0.65321	6.5	0.81291
0.6	-0.22184	2.6	0.41497	4.6	0.66275	6.6	0.81954
0.7	-0.15490	2.7	0.43136	4.7	0.67210	6.7	0.82607
0.8	-0.09691	2.8	0.44715	4.8	0.68124	6.8	0.83251
0.9	-0.04575	2.9	0.46239	4.9	0.69019	6.9	0.83885

n	log₁₀n	n	log₁₀n	n	log₁₀n
7.0	0.84509	9.0	0.95424	20.0	1.30103
7.1	0.85126	9.1	0.95904	21.0	1.32221
7.2	0.85733	9.2	0.96379	22.0	1.34242
7.3	0.86332	9.3	0.96848	23.0	1.36172
7.4	0.86923	9.4	0.97312	24.0	1.38021
7.5	0.87506	9.5	0.97772	25.0	1.39794
7.6	0.88081	9.6	0.98227	26.0	1.41497
7.7	0.88649	9.7	0.98677	27.0	1.43136
7.8	0.89209	9.8	0.99122	28.0	1.44715
7.9	0.89762	9.9	0.99563	29.0	1.46239
8.0	0.90309	10.0	1.00000	30.0	1.47711
8.1	0.90848	11.0	1.04139	40.0	1.60206
8.2	0.91381	12.0	1.07918	50.0	1.69897
8.3	0.91907	13.0	1.11394	60.0	1.77815
8.4	0.92428	14.0	1.14612	70.0	1.84509
8.5	0.92941	15.0	1.17609	80.0	1.90309
8.6	0.93450	16.0	1.20142	90.0	1.95424
8.7	0.93952	17.0	1.23044	100.0	2.00000
8.8	0.94448	18.0	1.25527	1000.0	3.00000
8.9	0.94939	19.0	1.27875	10000.0	4.00000