Modern Physics Chapter 1 Quiz

Classical physics excludes quantum mechanics and relativity; it includes Newtonian mechanics, thermodynamics, and electromagnetism.
Modern physics, starting around 1900, addresses concepts insufficiently explained by classical physics, utilizing relativity and quantum theories.

Classical kinetic energy formula: ( K = \frac{1}{2}mv^2 ), where ( K ) is kinetic energy, ( m ) is mass, and ( v ) is velocity.
Linear momentum is defined as ( p = mv ), where ( p ) is momentum (vector quantity), and ( v ) is velocity.
Kinetic energy can also be expressed in terms of linear momentum: ( K = \frac{p^2}{2m} ).

Conservation of Energy: In an isolated system, total energy remains constant; energy before a collision equals energy after.
Conservation of Linear Momentum: Total linear momentum of an isolated system is constant; momentum before equals momentum after in collisions.

Joule (J): ( 1 , \text{J} = 1 , \text{kg} \cdot \text{m}^2/\text{s}^2 )
Newton (N): ( 1 , \text{N} = \text{kg} \cdot \text{m/s}^2 )
Coulomb (C): ( 1 , \text{C} = 6.25 \times 10^{18} ) electrons
Farad (F): Capacitance, ( 1 , \text{F} = Q/V )
Watt (W): Power, ( 1 , \text{W} = \text{J/s} = \text{N} \cdot \text{m/s} )
Ampere (A): ( 1 , \text{A} = C/s )
Henry (H): ( 1 , \text{H} = \text{kg} \cdot \text{m}^2 \cdot \text{s}^{-2} \cdot \text{A}^{-2} )
Tesla (T): ( 1 , \text{T} = N/(A \cdot m) = N \cdot A^{-1} \cdot m^{-1} )

Force related to potential energy: ( F = \frac{dU}{dx} ), where ( U ) is potential energy.
Total energy of a system: ( E = U + K ), combining potential and kinetic energies.

Angular momentum formula: ( L = r \times p ), where ( L ) is angular momentum, ( r ) is displacement vector, and ( p ) is linear momentum vector.
Conservation of angular momentum states that this quantity remains constant unless acted upon by external torque.

Coulomb's law: ( F = \frac{1}{4\pi\varepsilon_0} \frac{|q_1||q_2|}{r^2} ), relates force between charged particles.
Permittivity of free space ( \varepsilon_0 = 8.85 \times 10^{-12} , \text{F/m} ); dielectric constant given by ( \varepsilon_r = \frac{\varepsilon_s}{\varepsilon_0} ).
Potential energy related to Coulomb force: ( U = \frac{1}{4\pi\varepsilon_0} \frac{q_1q_2}{r} ).

Potential difference definition: ( \Delta V = \frac{\Delta U}{q} ), measuring energy change per charge between two points.

An electron-volt (eV) is the energy gained by an electron moving through a potential difference of one volt; ( 1 , \text{eV} \approx 1.609 \times 10^{-19} , \text{J} ).

Magnetic flux unit: Weber (Wb), causing one volt in a circuit under specific conditions.
Permeability of free space ( \mu_0 = 4\pi \times 10^{-7} , \text{H} ); measures resistance to magnetic field formation in vacuum.
Magnetic field from a current: ( B = \frac{1}{2} \mu_0 i r^{-2} ).
Magnetic moment: ( |µ| = iA ), where ( A ) is the area of a closed loop.