Free Technology and Energy MCQs with Answers

81. Analytical solutions to Quadratic equations were introduced by__________?

• A. Al-Khawarzimi
• B. Al-haitham
• C. IsasacNewton
• D. Pythagoras

Explanation: Al-Khwarizmi gave systematic algebraic methods for solving quadratic equations, helping establish algebra as a distinct mathematical discipline. The other listed scientists are associated with different areas of mathematics or science.

82. Calculus was invented by________?

• A. Al-khawarzimi
• B. Pythagoras
• C. IsaaC Newton
• D. Al.kindi

Explanation: Isaac Newton is conventionally credited in basic science texts as a co-inventor of calculus, developed independently at about the same time as Gottfried Leibniz. Pythagoras and Al-Khwarizmi made major contributions to other mathematical fields.

83. Science is derived from Latin word "scientia" which means_________?

• A. Reasoning
• B. Logic
• C. Knowledge
• D. Life

Explanation: The Latin word scientia means “knowledge,” and it is the source of the modern word science. Reasoning and logic are methods used in science, not the literal meaning of scientia.

84. Air Conditioning Controls:___________?

• A. Circulation of the Air
• B. Humidity
• C. Temperature
• D. All of The Above

Explanation: An air conditioner regulates temperature, removes or adds moisture to control humidity, and circulates air through the room. Therefore all three functions are included.

85. In the electricity meter the digit to the extreme right is___________?

• A. 1/5th of the unit
• B. 1/100 of the unit
• C. 1/10th of the unit
• D. 1/1000th of the unit

Explanation: In the conventional household electricity meter described here, the extreme-right digit records tenths of a kilowatt-hour, so it represents 1/10 of a unit. Digital meters may show different decimal resolutions, but the traditional meter convention gives this answer.

86. Units of electricity consumed by 2500 watt air-conditioner in one hour are_________?

• A. 25 units
• B. 2.25 units
• C. 2.5 units
• D. 0.25 units

Explanation: Convert 2500 watts to 2.5 kilowatts, then multiply by one hour: 2.5 kW × 1 h = 2.5 kWh. Since one electricity unit equals one kilowatt-hour, the consumption is 2.5 units.

87. According to the definition of 1 KWh, a 100 watt bulb consumes one unit of electricity in_________?

• A. 2 hours
• B. 5 hours
• C. 8 hours
• D. 10 hours

Explanation: A 100-watt bulb uses 0.1 kilowatt, so it requires 10 hours to consume 1 kilowatt-hour, or one unit of electricity.

88. The large plates of solar pannels are painted?

• A. Red
• B. White
• C. Yellow
• D. Black

Explanation: Solar panels are painted black because black surfaces absorb the maximum amount of incoming sunlight and convert more of it into heat or electrical energy.

89. In which system of units, gas bills are charged?

• A. SI
• B. CGS
• C. BTU
• D. CNG

Explanation: Gas consumption is commonly expressed for billing in British thermal units, especially larger units such as MMBTU. SI and CGS are general measurement systems, while CNG is a fuel, not a unit.

90. In BTU system, one BTU is equal to__________?

• A. 2055 Joule
• B. 1155 Joule
• C. 2155 Joule
• D. 1055 Joule

Explanation: One British thermal unit is approximately equal to 1,055 joules, representing the heat needed to raise one pound of water by one degree Fahrenheit.