Crocodile Clips

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4. Output Displays – The LED array• An LED normally needs a forwardvoltage drop of 2V and sufficient lightis emitted with 10mA. A resistor isusually added to protect the LED fromdamage.• Activity 4: Find the value of theresistor needed to control the currentat 10mA when the supply voltage is5V. (Use JU1_LED)Extension:• Add an Ammeter in series with theLED, Resistor and find the safe currentwhich turns on the LED.• Fill in Answer here =• Now retry this with a voltage of 9V asshown opposite. What protectiveresistor is needed in this case?