15 extra multiple-choice questions for Recent Developments in Physics (12th Standard Physics, Samacheer Kalvi), beyond the ones printed in the textbook — each with the correct option highlighted and a clear, worked explanation. Free to read in English and Tamil.
Q1
Which field of study serves as the fundamental building block for modern advancements in engineering, technology, and medicine?
- A. Biology
- B. PhysicsCorrect
- C. Chemistry
- D. Mathematics
Explanation. Physics principles provide the essential foundation and framework upon which all major technological and medical breakthroughs are constructed.
Q2
In the context of nanoscience, what is the typical size range of the objects being studied?
- A. 1 to 100 micrometers
- B. 1 to 100 millimeters
- C. 1 to 100 nanometersCorrect
- D. 1 to 100 centimeters
Explanation. Nanoscience specifically investigates objects with dimensions between 1 and 100 nanometers, where one nanometer is equal to one-billionth of a meter.
Q3
Which of the following phenomena is primarily responsible for the striking difference in properties between a nano-form material and its bulk counterpart?
- A. Gravitational effects
- B. Magnetic resonance
- C. Quantum confinement effectsCorrect
- D. Thermal expansion
Explanation. Quantum confinement and surface effects are the two key governing factors that cause materials to behave differently at the nanoscale compared to larger scales.
Q4
As the size of a solid particle decreases toward the nanoscale, how does its surface-area-to-volume ratio change?
- A. It decreases significantly
- B. It remains constant
- C. It increases significantlyCorrect
- D. It first increases then decreases
Explanation. Reducing a material to smaller particles exposes a much higher percentage of its atoms to the surface, vastly increasing the surface-area-to-volume ratio.
Q5
The component of a robot that acts as its 'brain' and executes the programmed commands is the:
- A. Actuator
- B. Manipulator
- C. ControllerCorrect
- D. Sensor
Explanation. The controller is run by a computer program and issues the specific commands that guide the mechanical parts to perform their tasks.
Q6
What is the primary function of sensors within a robotic system?
- A. To provide power to the motors
- B. To gather information about the surroundingsCorrect
- C. To lift heavy loads
- D. To store the computer program
Explanation. Sensors allow the robot to perceive its environment, helping it determine the size, shape, and distance of objects and orientations.
Q7
Which type of industrial robot uses a 'Selective Compliance Assembly Robot Arm' and is ideal for assembly tasks?
- A. Cartesian robot
- B. Delta robot
- C. SCARA robotCorrect
- D. Polar robot
Explanation. SCARA robots feature joints that provide compliance in the horizontal plane while remaining rigid in the vertical direction, making them well-suited for assembly work.
Q8
What type of materials are commonly used to create 'muscle wires' for robot movements due to their ability to return to a pre-set shape?
- A. Simple copper alloys
- B. Shape memory alloysCorrect
- C. Pure silver wires
- D. Carbon fiber composites
Explanation. Shape memory alloys are used for muscle wires because they contract when heated and expand when cooled, allowing for precise robotic actuation.
Q9
In medical applications, virtual reality technology is effectively utilized for which of the following purposes?
- A. Monitoring blood glucose levels
- B. Stopping the brain from processing painCorrect
- C. Replacing damaged internal organs
- D. Detecting antibiotic resistance
Explanation. Medical virtual reality can distract and engage the brain, effectively preventing it from processing pain signals and reducing soreness in patients.
Q10
The emerging medical approach that customizes healthcare based on an individual's genes, environment, and lifestyle is known as:
- A. Telemedicine
- B. General radiology
- C. Precision medicineCorrect
- D. Nuclear medicine
Explanation. Precision medicine tailors medical treatments and practices to the individual patient by considering their unique biological and environmental variability.
Q11
What is a major advantage of using bio-resorbable wireless brain sensors in patient care?
- A. They provide 3D images of internal organs
- B. They never need to be calibrated
- C. They eliminate the need for a second surgery to remove themCorrect
- D. They can be powered by light pulses
Explanation. Because these sensors are absorbed by the body after monitoring intracranial pressure and temperature, surgery for their removal is not required.
Q12
According to the quark model, which smaller fundamental entities combine to form protons and neutrons?
- A. Positrons
- B. QuarksCorrect
- C. Neutrinos
- D. Photons
Explanation. Particle physics has established that nucleons like protons and neutrons are not fundamental but are instead composed of constituent particles called quarks.
Q13
Which particle, sometimes called the 'God' particle, was discovered in 2013 and is responsible for providing mass to other particles?
- A. Gluon
- B. Neutrino
- C. Higgs particleCorrect
- D. Electron
Explanation. The discovery of the Higgs particle was a landmark event because it provides the mechanism by which many fundamental particles gain their mass.
Q14
At what speed do gravitational waves travel through the curvature of space-time?
- A. Speed of sound
- B. Half the speed of light
- C. Speed of lightCorrect
- D. Infinite speed
Explanation. Gravitational waves are disturbances in spacetime that propagate as waves at the universal speed of light, as predicted by general relativity.
Q15
In quantum computing, what is the basic unit of information that can exist as 0, 1, or a linear superposition of both?
- A. Binary bit
- B. Byte
- C. QubitCorrect
- D. Macrobit
Explanation. A qubit (quantum bit) represents the basic unit of information in quantum systems, allowing for significantly more complex calculations than classical bits.
Frequently asked questions
How many MCQs are there in Recent Developments in Physics?
This chapter has 15 book-back multiple-choice questions, each with the correct answer and a step-by-step explanation.
Are these 12th Standard Physics MCQs free to practise online?
Yes. Every question, answer and explanation here is free, and you can also take them as a timed practice test.
Where can I find the Recent Developments in Physics book-back answers?
The correct option for each question is highlighted on this page with a worked explanation, plus a quick answer-key summary at the top.
