Free Technology and Energy MCQs with Answers

1. In electronics, LED stands for:

• A. Light Emitting Diode
• B. Low Energy Device
• C. Linear Electric Display
• D. Light Enhanced Detector

Explanation: LED stands for Light Emitting Diode — a semiconductor that emits light when current flows through it in the forward direction. LEDs consume far less power than incandescent bulbs, which is why they dominate lighting and display technology.

2. Which of the following source of energy is caused by uneven heating of earth's surface?

• A. Wind
• B. Solar
• C. Biomass
• D. None of these

Explanation: Uneven heating of Earth creates differences in air pressure, causing air to move from high-pressure to low-pressure regions as wind. Solar energy is the original source, but wind is the energy form directly produced by this uneven heating.

3. A device that converts mechanical energy into electric energy is called_______?

• A. Motor.
• B. Transformer.
• C. Coil.
• D. Generator.

Explanation: A generator uses mechanical motion to produce electrical energy through electromagnetic induction. A motor does the reverse by converting electrical energy into mechanical energy.

4. Copper is used in the production of___________?

• A. Brick kilns
• B. Children toys
• C. Kitchen utilities
• D. Electric wires

Explanation: Copper is highly useful for electric wires because it conducts electricity well and can be drawn into thin, flexible wires. Its conductivity makes it more suitable for wiring than for the other listed uses.

5. Vacuum tubes have been replaced by__________?

• A. Conductors
• B. Diodes
• C. Transistors
• D. None of these

Explanation: Transistors replaced bulky, fragile vacuum tubes because they are smaller, more reliable, require less power and produce less heat. Diodes are semiconductor components but are not the general replacement referred to here.

6. One of the following countries produces maximum energy from atomic reactors?

• A. France
• B. USA
• C. UK
• D. none

Explanation: The United States has generally produced the greatest total amount of nuclear-generated electricity because it operates a large nuclear reactor fleet. France often leads in the percentage of its electricity supplied by nuclear power, which is a different comparison.

7. Basha Dam is to be constructed on___________?

• A. River Sutlaj
• B. River Jhelum
• C. River Chenab
• D. None (On Indus River in Gilgit-Baltistan)

Explanation: The Diamer-Bhasha Dam is planned on the Indus River in Gilgit-Baltistan, not on the Sutlej, Jhelum or Chenab. Therefore, the stated 'None' option is correct.

8. What is 'Stealth Technology'?

• A. A device which when attached to an aircraft makes it invisible on the radar
• B. A coating which reduces the visibility of an aircraft on radar
• C. A Technology by which it is possible for the aircraft's to spy in the enemy air-space
• D. A technology by using which paratroopers can be dropped stealthily behind the enemy columns.

Explanation: Stealth technology reduces an aircraft's radar signature through shaping, radar-absorbing materials and other design measures. A special coating can contribute to this reduction, but stealth is not simply a device that makes an aircraft completely invisible.

9. A nuclear reactor is a device used to carry out controlled nuclear reaction whereas GM counter is a device used to detect?

• A. Current
• B. Voltage
• C. Nuclear Radiation
• D. power
• E. None of these

Explanation: A Geiger-Müller counter detects ionising nuclear radiation such as alpha, beta and gamma radiation. It does not measure ordinary electrical quantities like current or voltage.

10. In a fission nuclear reaction , a heavy nucleus breaks up into smaller nuclei whereas in another nuclear reaction two or more than two possibly nuclei are fused to form a heavy nucleus This nuclear reaction is called ?

• A. Chemical Reaction
• B. Nuclear reaction
• C. Fission nuclear reaction
• D. Fusion nuclear reaction
• E. None of these

Explanation: Nuclear fusion joins two or more light nuclei to form a heavier nucleus and releases energy. Fission is the opposite process, in which a heavy nucleus splits into smaller nuclei.