Physics

The SI unit of heat is the joule (J), which is the standard unit of energy in the International System of Units. Heat is a form of energy transfer, so it is measured in joules.

The SI unit of electric current is the ampere, which measures the flow of electric charge per second. Coulomb is the unit of electric charge, volt is the unit of electric potential, and watt is the unit of power.

Einstein's famous equation is E = mc², which shows that energy (E) and mass (m) are interchangeable, with c representing the speed of light squared. This equation is fundamental in physics and correctly expresses the mass-energy equivalence.

Max Planck was awarded the Nobel Prize in Physics in 1918 for his discovery of energy quanta, which laid the foundation for quantum theory.

Dr. Abdus Salam was a key contributor to the electroweak theory, which unifies the electromagnetic force and the weak nuclear force. This unification is a fundamental part of the Standard Model of particle physics.

One light year is the distance light travels in one year, which is approximately 9.5×10^12 kilometers. This matches option C, making it the correct answer.

Escape velocity depends on the mass and radius of a celestial body. Since the Moon has less mass and a smaller radius than Earth, its escape velocity is lower than Earth's.

A magnetometer is an instrument used to measure magnetic fields, including changes in the Earth's magnetic field. This makes option C the correct answer.

Authoritative sources including NASA and Space.com confirm that when the Sun exhausts its hydrogen fuel in about 5 billion years, it will expand into a red giant. This expansion will engulf the inner planets Mercury and Venus for sure, and most models indicate it will also engulf Earth. The fate of Mars is less certain, but it is generally considered unlikely to be engulfed. The outer planets (Jupiter, Saturn, Uranus, Neptune) will not be swallowed but will move outward due to the Sun losing mass. Therefore, the most accurate answer is C: The sun will then expand into a red giant and possibly swallow the inner planets, including Earth. Option B is incorrect because the outer planets will not be engulfed by the Sun's red giant phase.

Escape velocity depends only on the mass and radius of the Earth, not on the object's mass or type. Therefore, both a pen and a home require the same escape velocity to leave Earth.