How a Remote Control Works ? : ā§°āĻŋāĻŽā§‹āϟ āĻ•āĻ¨ā§āĻŸā§ā§°ā§‹āϞ āϕ⧇āύ⧇āĻ•ā§ˆ āĻ•āĻžāĻŽ āϕ⧰⧇ ?


Definition : A remote control is a device used to operate electronic appliances (like TV) from a distance using infrared signals. ā§°āĻŋāĻŽā§‹āϟ āĻ•āĻ¨ā§āĻŸā§ā§°ā§‹āϞ āĻšā§ˆāϛ⧇ āĻāϟāĻž āϝāĻ¨ā§āĻ¤ā§ā§° āϝāĻŋ āĻĻā§‚ā§°āĻ¤ā§āĻŦā§° āĻĒā§°āĻž āϟāĻŋāĻ­āĻŋ āφāĻĻāĻŋ āύāĻŋāϝāĻŧāĻ¨ā§āĻ¤ā§ā§°āĻŖ āϕ⧰⧇, infrared āϏāĻ‚āϕ⧇āϤ āĻŦā§āĻ¯ā§ąāĻšāĻžā§° āϕ⧰āĻŋāĨ¤


Main Parts


Buttons → Used to give command : āĻŦ⧁āϟāĻžāĻŽ āϟāĻŋāĻĒāĻŋ āύāĻŋā§°ā§āĻĻ⧇āĻļ āĻĻāĻŋāϝāĻŧāĻž āĻšāϝāĻŧ


Control Circuit → Processes the command : āύāĻŋā§°ā§āĻĻ⧇āĻļ āĻĒā§ā§°āĻ•ā§ā§°āĻŋāϝāĻŧāĻž āϕ⧰⧇


IR LED (Transmitter) → Sends signal : āϏāĻ‚āϕ⧇āϤ āĻĒāĻ āĻžāϝāĻŧ


TV Receiver (Sensor) → Receives signal : āϏāĻ‚āϕ⧇āϤ āĻ—ā§ā§°āĻšāĻŖ āϕ⧰⧇


Working Steps


1. Button Press : User presses a button : āĻŦā§āĻ¯ā§ąāĻšāĻžā§°āĻ•āĻžā§°ā§€āϝāĻŧ⧇ āĻŦ⧁āϟāĻžāĻŽ āϟāĻŋāĻĒ⧇


2. Signal Sending : Remote sends infrared signal : ā§°āĻŋāĻŽā§‹āĻŸā§‡ infrared āϏāĻ‚āϕ⧇āϤ āĻĒāĻ āĻžāϝāĻŧ


3. Signal Travel : Signal travels to the TV : āϏāĻ‚āϕ⧇āϤ āϟāĻŋāĻ­āĻŋāϞ⧈ āϝāĻžāϝāĻŧ


4. Signal Receiving : TV receiver detects signal : āϟāĻŋāĻ­āĻŋāϝāĻŧ⧇ āϏāĻ‚āϕ⧇āϤ āĻ—ā§ā§°āĻšāĻŖ āϕ⧰⧇


5. Processing : TV processes the command : āϟāĻŋāĻ­āĻŋāϝāĻŧ⧇ āύāĻŋā§°ā§āĻĻ⧇āĻļ āĻŦ⧁āĻœā§‡


6. Output Action : Action happens (volume/channel change) : āĻ•āĻžāĻŽ āĻšāϝāĻŧ (āĻ­āϞāĻŋāωāĻŽ/āĻšā§‡āύ⧇āϞ āϏāϞāύāĻŋ)


Important Concept


Infrared Signal : Invisible light waves used for short-distance communication. : āĻ…āĻĻ⧃āĻļā§āϝ āφāϞ⧋āĻ• āϤ⧰āĻ‚āĻ—, āϏ⧰⧁ āĻĻā§‚ā§°āĻ¤ā§āĻŦā§° āϝ⧋āĻ—āĻžāϝ⧋āĻ—āϤ āĻŦā§āĻ¯ā§ąāĻšāĻžā§° āĻšāϝāĻŧ


Revision Points



  • Button → Signal → Receiver → Action

  • Uses Infrared (IR)

  • Works only in short distance

  • Needs direct line (no obstacle)


Ans: A remote control works by sending infrared signals to control a device from a distance.


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MCQs – Remote Control


Q1. What is the main function of a remote control ? ā§°āĻŋāĻŽā§‹āϟ āĻ•āĻ¨ā§āĻŸā§ā§°ā§‹āϞ⧰ āĻŽā§‚āϞ āĻ•āĻžāĻŽ āĻ•āĻŋ ?
(A) Cooking (B) Controlling devices (C) Heating (D) Cooling


Ans: (B) Controlling devices


Explanation: It controls electronic devices like TV. āĻŦā§āϝāĻžāĻ–ā§āϝāĻž: āϟāĻŋāĻ­āĻŋ āφāĻĻāĻŋ āύāĻŋāϝāĻŧāĻ¨ā§āĻ¤ā§ā§°āĻŖ āϕ⧰⧇āĨ¤


Q2. Which signal is used in remote control ? ā§°āĻŋāĻŽā§‹āϟāϤ āϕ⧋āύ āϏāĻ‚āϕ⧇āϤ āĻŦā§āĻ¯ā§ąāĻšāĻžā§° āĻšāϝāĻŧ ? 
(A) Sound (B) Infrared (C) Radio (D) Magnetic


Ans: (B) Infrared
Explanation: Uses infrared signals. āĻŦā§āϝāĻžāĻ–ā§āϝāĻž: Infrared āϏāĻ‚āϕ⧇āϤ āĻŦā§āĻ¯ā§ąāĻšāĻžā§° āĻšāϝāĻŧāĨ¤


Q3. Infrared signals are ? Infrared āϏāĻ‚āϕ⧇āϤ āϕ⧇āύ⧇āϧ⧰āĻŖā§° ?
(A) Visible (B) Invisible (C) Solid (D) Liquid


Ans: (B) Invisible
Explanation: They are invisible light waves. āĻŦā§āϝāĻžāĻ–ā§āϝāĻž: āĻāχāĻŦā§‹ā§° āĻ…āĻĻ⧃āĻļā§āϝ āφāϞ⧋āĻ• āϤ⧰āĻ‚āĻ—āĨ¤


Q4. What happens when a button is pressed ? Button āϟāĻŋāĻĒāĻŋāϞ⧇ āĻ•āĻŋ āĻšāϝāĻŧ ?
(A) Light off (B) Signal sent (C) Sound made (D) Heat produced


Ans: (B) Signal sent
Explanation: Remote sends signal. āĻŦā§āϝāĻžāĻ–ā§āϝāĻž: āϏāĻ‚āϕ⧇āϤ āĻĒāĻ ā§‹ā§ąāĻž āĻšāϝāĻŧāĨ¤


Q5. Which part sends the signal ? āϕ⧋āύ āĻ…āĻ‚āĻļ⧇ āϏāĻ‚āϕ⧇āϤ āĻĒāĻ āĻžāϝāĻŧ ?
(A) Receiver (B) Motor (C) IR LED (D) Screen


Ans: (C) IR LED
Explanation: IR LED transmits signal. āĻŦā§āϝāĻžāĻ–ā§āϝāĻž: IR LED-āĻ āϏāĻ‚āϕ⧇āϤ āĻĒāĻ āĻžāϝāĻŧāĨ¤


Q6. Which part receives the signal ? āϕ⧋āύ āĻ…āĻ‚āĻļ⧇ āϏāĻ‚āϕ⧇āϤ āĻ—ā§ā§°āĻšāĻŖ āϕ⧰⧇ ?
(A) Remote (B) Sensor (TV receiver) (C) Battery (D) Button


Ans: (B) Sensor (TV receiver)
Explanation: Sensor detects signal. āĻŦā§āϝāĻžāĻ–ā§āϝāĻž: āϏ⧇āĻ¨ā§āϏ⧰⧇ āϏāĻ‚āϕ⧇āϤ āϞāϝāĻŧāĨ¤


Q7. Remote works best in ? ā§°āĻŋāĻŽā§‹āϟ āĻ­āĻžāϞāĻ•ā§ˆ āĻ•āĻžāĻŽ āϕ⧰⧇ āĻ•’āϤ ?
(A) Long distance (B) Short distance (C) Underground (D) Water


Ans: B
Explanation: Works in short range. āĻŦā§āϝāĻžāĻ–ā§āϝāĻž: āϏ⧰⧁ āĻĻā§‚ā§°āĻ¤ā§āĻŦāϤ āĻ•āĻžāĻŽ āϕ⧰⧇āĨ¤


Q8. What is needed for proper working ? āϏāĻ āĻŋāĻ• āĻ•āĻžāĻŽā§° āĻŦāĻžāĻŦ⧇ āĻ•āĻŋ āϞāĻžāϗ⧇ ?
(A) Obstacle (B) Direct line (C) Water (D) Heat


Ans: (B) Direct line
Explanation: Needs clear path. āĻŦā§āϝāĻžāĻ–ā§āϝāĻž: āĻŽāĻžāϜāϤ āĻŦāĻžāϧāĻž āύāĻžāĻĨāĻžāĻ•āĻŋāĻŦ āϞāĻžāϗ⧇āĨ¤


Q9. Which part processes the signal ? āϏāĻ‚āϕ⧇āϤ āϕ⧋āύ⧇ āĻĒā§ā§°āĻ•ā§ā§°āĻŋāϝāĻŧāĻž āϕ⧰⧇ ?
(A) Button (B) Circuit (C) LED (D) Wire


Ans: (B) Circuit
Explanation: Circuit processes command. āĻŦā§āϝāĻžāĻ–ā§āϝāĻž: āϚāĻžā§°ā§āĻ•āĻŋāĻŸā§‡ āύāĻŋā§°ā§āĻĻ⧇āĻļ āĻŦ⧁āĻœā§‡āĨ¤


Q10. What action can be done using remote ? ā§°āĻŋāĻŽā§‹āĻŸā§‡ āĻ•āĻŋ āϕ⧰āĻŋāĻŦ āĻĒāĻžā§°ā§‡ ?
(A) Washing (B) Cooking (C) Volume change (D) Writing


Ans: (C) Volume change
Explanation: Controls volume/channel. āĻŦā§āϝāĻžāĻ–ā§āϝāĻž: āĻ­āϞāĻŋāωāĻŽ/āĻšā§‡āύ⧇āϞ āϏāϞāύāĻŋ āϕ⧰⧇āĨ¤


Q11. Signal travels from ? āϏāĻ‚āϕ⧇āϤ āĻ•’ā§° āĻĒā§°āĻž āĻ•’āϞ⧈ āϝāĻžāϝāĻŧ ?
(A) TV to remote (B) Remote to TV (C) Battery to wire (D) Screen to button


Ans: (B) Remote to TV
Explanation: Signal goes to TV. āĻŦā§āϝāĻžāĻ–ā§āϝāĻž: ā§°āĻŋāĻŽā§‹āϟ⧰ āĻĒā§°āĻž āϟāĻŋāĻ­āĻŋāϞ⧈ āϝāĻžāϝāĻŧāĨ¤


Q12. Remote control uses ? ā§°āĻŋāĻŽā§‹āϟ āĻ•āĻ¨ā§āĻŸā§ā§°ā§‹āϞ⧇ āĻ•āĻŋ āĻŦā§āĻ¯ā§ąāĻšāĻžā§° āϕ⧰⧇ ?
(A) Heat (B) Light waves (C) Water (D) Gas


Ans: (B) Light waves
Explanation: Uses infrared light waves. āĻŦā§āϝāĻžāĻ–ā§āϝāĻž: āφāϞ⧋āĻ• āϤ⧰āĻ‚āĻ— āĻŦā§āĻ¯ā§ąāĻšāĻžā§° āϕ⧰⧇āĨ¤


Q13. First step of working is ? āĻĒā§ā§°āĻĨāĻŽ āϧāĻžāĻĒ āĻ•āĻŋ ?
(A) Signal received (B) Button press (C) Action (D) Processing


Ans: (B) Button press
Explanation: User presses button first. āĻŦā§āϝāĻžāĻ–ā§āϝāĻž: āĻĒā§ā§°āĻĨāĻŽā§‡ āĻŦ⧁āϟāĻžāĻŽ āϟāĻŋāĻĒ⧇āĨ¤


Q14. Last step of working is ? āĻļ⧇āώ āϧāĻžāĻĒ āĻ•āĻŋ ?
(A) Signal send (B) Receive (C) Action performed (D) Button press


Ans: (C) Action performed
Explanation: Device performs action. āĻŦā§āϝāĻžāĻ–ā§āϝāĻž: āĻļ⧇āώāϤ āĻ•āĻžāĻŽ āĻšāϝāĻŧāĨ¤


Q15. Remote cannot work when ? ā§°āĻŋāĻŽā§‹āϟ āĻ•āĻžāĻŽ āύāϕ⧰⧇ āϕ⧇āϤāĻŋāϝāĻŧāĻž ?
(A) Direct line present (B) Battery full (C) Obstacle present (D) Close distance


Ans: (C) Obstacle present
Explanation: Obstacle blocks signal. āĻŦā§āϝāĻžāĻ–ā§āϝāĻž: āĻŦāĻžāϧāĻžāχ āϏāĻ‚āϕ⧇āϤ āĻŦāĻ¨ā§āϧ āϕ⧰⧇āĨ¤