Measuring & Amplifying a Resistance

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i have number of sensors change resistance when interact them (ldr, flex sensor, load cell etc.). i'm wondering is:

1. what's best way measure resistance? should use voltage divider or wheatstone bridge or else? value resistors should use?

2. how can amplify signal? possible use transistor?

thanks.

the normal way use devices part of voltage divider. connect them this

       arduino 5v pin -----------ldr----------x-----------fixed resistor----------arduino gnd

then use analog input measure voltage @ x using analogread(). when know voltage @ x can calculate other values.

i don't understand think needs amplified? can't amplify resistance.

...r


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