Physics

The dimensional formula ML⁻¹T⁻² corresponds to force per unit area, which is the dimension of pressure. Force has the dimension ML¹T⁻², and dividing by area (L²) gives ML⁻¹T⁻². This dimension also corresponds to energy per unit volume, but among the given options, pressure is the correct match. Momentum has the dimension MLT⁻¹, energy has ML²T⁻², and force has ML¹T⁻², so they do not match ML⁻¹T⁻².

Antimatter is composed of antiparticles corresponding to normal matter particles, including antiprotons, antineutrons, and positrons. Therefore, all the listed particles are components of antimatter.

For a chain reaction to sustain and build up, the size of the radioactive target must be greater than the critical size. This ensures enough neutrons are produced and maintained to continue the reaction.

Neutrons and protons are collectively known as nucleons because they both reside in the nucleus of an atom. This term distinguishes them from other particles like mesons, bosons, or quartz, which are unrelated to nucleons.

Alpha particles, which are helium nuclei, interact with atoms primarily by ionizing them. This ionization process involves knocking out electrons from the atom, not protons or neutrons. Protons and neutrons are bound tightly within the nucleus and are not typically knocked out by alpha particles during ordinary encounters. Alpha particles have enough energy to remove electrons from atoms, causing ionization, but they do not generally dislodge nucleons (protons or neutrons) unless in specific nuclear reactions or high-energy collisions, which are not the usual context of the question.

A Geiger counter is best suited for slow counting rates because it has a limited resolving time and cannot accurately measure very high or extremely fast counting rates without significant dead time losses.

The number 0.0173 has three significant figures: 1, 7, and 3. Leading zeros are not counted as significant figures.

The dimension of force is given by mass × acceleration. Mass has dimension M, and acceleration has dimension LT⁻², so force has dimension MLT⁻², which corresponds to option B.

The curie (Ci) is defined as 3.7 × 10^10 disintegrations per second, which is the standard unit of radioactivity. Option B correctly states this value.

Gamma rays are highly penetrating electromagnetic radiation, which allows them to pass through materials and effectively kill bacteria and other microorganisms, making them suitable for sterilizing surgical equipment.

The average distance an alpha particle travels in air before losing its ionizing power is called its 'range'. This term specifically refers to how far the particle can penetrate before it stops ionizing the medium.

Alpha particles (α-rays) are helium nuclei and have mass, traveling at about 5% to 10% of the speed of light. Beta particles (β-rays) are high-energy electrons or positrons that can travel at speeds close to but less than the speed of light, typically around 0.9c to 0.99c. Gamma rays (γ-rays) are electromagnetic radiation and travel at the speed of light in vacuum, which is the maximum possible speed. Therefore, γ-rays possess the maximum velocity among the given options.

A neutron is a subatomic particle with no net electric charge, meaning its charge is zero. This distinguishes it from protons (positive charge) and electrons (negative charge).

Physics is fundamental to technology and engineering because it studies the principles governing matter and energy, which are essential for designing and understanding technological devices and engineering systems.

Radioactivity is a nuclear phenomenon because it originates from changes in the nucleus of an unstable atom. It is a spontaneous process and does not depend on chemical reactions or external conditions like temperature or pressure.

Static equilibrium refers to a state where an object is at rest and all forces and torques are balanced, so there is no motion. Dynamic equilibrium involves motion with balanced forces or torques. Therefore, static equilibrium is not a type of dynamic equilibrium.

A mass spectrograph (or mass spectrometer) sorts out ions based on their mass-to-charge ratio, allowing the identification and analysis of different ions in a sample.

Gamma rays (γ-rays) have the highest penetrating power among the listed types of radiation because they have the shortest wavelength and highest energy, allowing them to penetrate materials more deeply than X-rays or beta rays.

Robert Millikan determined the charge of an electron through his famous oil drop experiment, which measured the elementary electric charge accurately.

Torque is defined as the product of force and the perpendicular distance from the axis of rotation (lever arm). Force has the dimension [MLT^{-2}] and distance has the dimension [L]. Therefore, the dimension of torque is the product of these, which is [ML^2T^{-2}]. This matches option A. Option B corresponds to the dimension of force, not torque.

Random errors arise from unpredictable fluctuations in measurement and can be minimized by taking the mean of several measurements, which averages out the random variations.

Pair production requires the presence of a nearby nucleus or particle to conserve momentum. In a vacuum, momentum cannot be conserved during pair production, so it cannot occur there.

When nitrogen is bombarded with alpha particles, a nuclear reaction occurs producing an oxygen isotope and a proton. This is a classic example of a nuclear reaction where an alpha particle (helium nucleus) collides with nitrogen, ejecting a proton.

During the fusion of hydrogen into helium, nuclear reactions convert mass into energy, releasing a significant amount of energy. This is why stars, including the Sun, emit energy through fusion.

Nuclear forces, also known as strong nuclear forces, act between all nucleons—protons and neutrons—inside the nucleus. Therefore, they exist between proton-proton, proton-neutron, and neutron-neutron pairs, making 'All of the above' the correct answer.