which of the signals below is a digital signal? 1. 2. 3. 4. 5. 40
TRANSCRIPT
The box below contains components used in electronics
The box contains:
Capacitor, thermistor, loudspeaker, relay ,potential divider, LED, solar cell
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2. 3 input devices and 4 output devices
3. 4 input devices and 3 output devices
4. 5 input devices and 2 output devices
5. 6 input devices and 1 output devices
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A resistor is usually placed in series with a LED to
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20%
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2. Give the current an alternative path
3. Reduce the voltage flowing through the LED
4. Increase the brightness of the LED
5. Reduce the current flowing through the LED
Which of the components below would be a suitable input device for a public address system at sports
day
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20%1. Relay
2. Buzzer
3. Solenoid
4. Loudspeaker
5. Microphone
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This is the symbol for which electronic component?
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20%1. A NOT gate
2. An AND gate
3. An OR gate
4. A light dependent resistor
5. A light emitting diode
In the circuit when the switch is closed the reading on the voltmeter rises slowly to 6v.
Which of the following
components could X be?
X
V
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20%1. Capacitor
2. Resistor
3. Bulb
4. Diode
5. LED
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When this circuit is switched on the bulb lights dimly and the LED is bright.
What would happen if the battery connections were reversed?
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20%1. The bulb goes out2. The LED burns out3. the bulb becomes a little duller4. the bulb becomes a little brighter5. The bulb and the LED go out
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Which single digit number on a seven segment display uses the most segments
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20%1. Three
2. Four
3. Five
4. Eight
5. Nine
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A solar cell changes
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2. Light energy to electrical energy
3. Light energy to chemical energy
4. Heat energy to electrical energy
5. Heat energy to light energy
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A Thermistor has a resistance of 1000Ω at 300oC and 2000Ω at 1000C. It is connected to a 3V supply. What could be the current in the circuit at 2000C?
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20%1. 0.5mA
2. 1.0mA
3. 1.5mA
4. 2.0mA
5. 3.0mA
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In this circuit V1 reads 2v and V2 reads 7v. If the light level was increased, what could be the new readings on V1 and V2?
V1
V2
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20%1. 1v and 8v
2. 2v and 5v
3. 2v and 8v
4. 4v and 5v
5. 5v and 4v
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When 11binary is multiplied by 11binary the answer in binary is
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2. 101
3. 121
4. 1000
5. 1001
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XYThe circuit above was designed to switch a LED on when
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20%1. Switch X is on and switch Y is not on
2. Switch X is not on and switch Y is on
3. Switch X is on or switch Y is on
4. Switch X is not on or switch Y is not on
5. Switch X is not on and switch Y is not on
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This circuit is designed to:
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2. Produce a power gain
3. Produce clock pulses
4. Produce a switched circuit
5. Produce a high voltage
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An amplifier has a voltage gain of 5. If the input voltage is 12mv and the input current is
2mA, the output voltage of the amplifier is
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20%1. 10mv
2. 17mv
3. 24mv
4. 60mv
5. 120mv
Which of the following appliances does not have an amplifier?
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2. CD player
3. Television
4. Telephone
5. Satellite receiver
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What is the least number of switches that must be closed to light the LED
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2.
3.
4.
5.
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A voltage from a signal generator is fed into an oscilloscope and the pattern to the right is obtained.If voltage is now fed into an amplifier with a gain of 2, what would
the pattern look like ?
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25% 1. 2. 3. 4.
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