Given 1/f = 1/So + 1/Si, where f = 15 cm and So = 20 cm (second significant digit). Find Si.
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Oh! N: Those danged old problems they give you. Let's fool em.
1/15= 1/20 +1/Si' We multiply both sides by 15 to get 15/15 =15/20 +15/Si
1=3/4 +15/Si; 1-3/4= 1/4=15/Si; We multiply both sides by 4Si to get 4/4Si=60 and since 4/4=1 we get Si =60; We prove: 1/15 =1/20 +1/60 ; 1/15=3/60 +1/60=4/60 =1/15. N: We could have simply done some cross multiplications and made this shorter; however I wished to go this route so you can see how a law of equati0ons worked. ie Equations are like a balance scale.: One can add, subtract, multiply , divide, change signs on one side of any equation using any value and the equation will remain correct as long as one does the exact same thing to the other side using the exact same value. Hope this helps. Go0od Luck
1/15= 1/20 +1/Si' We multiply both sides by 15 to get 15/15 =15/20 +15/Si
1=3/4 +15/Si; 1-3/4= 1/4=15/Si; We multiply both sides by 4Si to get 4/4Si=60 and since 4/4=1 we get Si =60; We prove: 1/15 =1/20 +1/60 ; 1/15=3/60 +1/60=4/60 =1/15. N: We could have simply done some cross multiplications and made this shorter; however I wished to go this route so you can see how a law of equati0ons worked. ie Equations are like a balance scale.: One can add, subtract, multiply , divide, change signs on one side of any equation using any value and the equation will remain correct as long as one does the exact same thing to the other side using the exact same value. Hope this helps. Go0od Luck
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1/Si = 1/f - 1/So = 1/15 - 1/20 = 4/60 - 3/60 = 1/60, so Si=60.
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I was never good at math sorry I wish i could help
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I was never good at math sorry I wish i could help