GRE Physics Practice Test

A block of mass \( m \) is on a frictionless inclined plane of angle \( \theta \). What is the acceleration of the block down the slope?

A particle moves in a circle of radius \( r \) with constant speed \( v \). What is the magnitude of the acceleration of the particle?

In a system of particles, the total momentum is conserved if:

A rigid body rotates about a fixed axis with a constant angular acceleration. Which of the following is true regarding the tangential acceleration of any point on the body?

The work done in slowly lifting an object to a height \( h \) against gravity is equal to:

What is the angular frequency of a mass-spring system with mass \( m \) and spring constant \( k \)?

A ball is thrown vertically upward with velocity \( v \). What is the time taken to reach its highest point?

A planet orbits a star in an elliptical orbit. At which point is the planet's kinetic energy maximum?

What is the period of a simple pendulum of length \( L \) and negligible mass bob at a place where acceleration due to gravity is \( g \)?

A pendulum of length \( L \) swings with a small amplitude in a gravitational field \( g \). What is the linear acceleration \( a \) at the lowest point of the swing?

For a satellite in a stable circular orbit around Earth, the orbital speed is dependent on:

A particle of mass \( m \) is moving in a circular path of radius \( r \) with a constant speed \( v \). What is the angular momentum of the particle about the center of the circle?

Two objects with masses \( m_1 \) and \( m_2 \) are connected by a light string over a frictionless pulley. If \( m_1 > m_2 \), what is the acceleration of the system? (Assume \( g \) is the acceleration due to gravity.)

A solid sphere and a hollow sphere, both of the same mass and radius, roll down an inclined plane. Which one reaches the bottom first?

Which of the following best describes the principle of superposition in the context of electric fields?

Which of the following is true for the electric field inside a conductor in electrostatic equilibrium?

What happens to the capacitance of a parallel-plate capacitor when a dielectric material is inserted between the plates?

How does the frequency of light change as it passes from air into water?

In an AC circuit containing only a capacitor, what is the phase difference between the current and the voltage across the capacitor?

What is the self-inductance of a solenoid directly proportional to?

In a region of space, a uniform magnetic field passes perpendicularly through a rectangular loop of wire. If the magnetic field is steadily increasing, what is the direction of the induced current in the loop?

What is the magnetic field at the center of a circular loop of wire carrying a steady current?

What is the SI unit of magnetic flux?

What is the force between two parallel current-carrying wires when the currents are in opposite directions?

Which of the following is not a characteristic of electromagnetic waves?

What is the main effect of increasing the frequency of an alternating current in a purely resistive circuit?

What is the magnetic field at the center of a circular loop of wire carrying a steady current?

A ray of light in air strikes a glass surface at an angle less than the critical angle. What happens to the ray?

A beam of unpolarized light is incident on a polarizer. What fraction of the light's intensity is transmitted through the polarizer?

What is the Brewster's angle for a medium with a refractive index of 1.5?

Which color of light has the shortest wavelength when passing through a prism?

What property of a wave remains constant as it passes from one medium to another?

In an optical fiber, light is confined within the core by the principle of:

Which principle is best illustrated by the operation of a heat pump?

What does the Stefan-Boltzmann law relate to in thermodynamics?

In a reversible process, how does the entropy change in the universe?

What is the primary implication of the Third Law of Thermodynamics?

A Carnot engine operates between two reservoirs at temperatures \( T_1 \) and \( T_2 \) (\( T_1 > T_2 \)). If the efficiency of the engine is 40\%, what is the ratio \( \frac{T_1}{T_2} \)?

What is the significance of the Boltzmann constant in statistical mechanics?

In a thermodynamic process, a gas expands from volume \( V_1 \) to \( V_2 \) and absorbs \( Q \) amount of heat. If the work done by the gas is \( W \) and the change in internal energy is \( \Delta U = 0 \), what is the relationship between \( Q \) and \( W \)?

A particle in a one-dimensional box of width \( L \) is in a state described by the wave function \( \psi(x) = A \sin(\frac{2\pi x}{L}) \). What is the energy of the particle?

If a quantum system is described by the normalized wave function \( \psi(x) \), what is the probability of finding the particle in the interval \( a \leq x \leq b \)?

What is the probability of finding a particle in the ground state in a one-dimensional box of length \( L \) between \( \frac{L}{4} \) and \( \frac{3L}{4} \)?

Which of the following represents the correct commutation relation between position (\( \hat{x} \)) and momentum (\( \hat{p} \)) operators?

What is the uncertainty in position (\( \Delta x \)) for a particle if the uncertainty in its momentum (\( \Delta p \)) is known to be \( \frac{\hbar}{2} \)?

Which principle states that no two fermions can occupy the same quantum state?

For a particle in a three-dimensional spherical box, the energy eigenfunctions are labeled by quantum numbers \( n, l, \) and \( m \). What is the degeneracy of the energy level characterized by quantum number \( n \)?

In the context of quantum mechanics, what does the term 'orthonormality' refer to?

In quantum mechanics, what does the operator \( \hat{H} \) represent?

What happens to the energy levels of an atom in a strong magnetic field (Zeeman effect)?

In a hydrogen atom, which electronic transition corresponds to the emission of the longest wavelength photon?

Which phenomenon demonstrates the wave-particle duality of electrons?

In atomic physics, what does the fine structure of spectral lines primarily result from?

In the context of quantum mechanics, which principle states that it is impossible to simultaneously know both the exact momentum and position of a particle?

Which type of quantum numbers are used to describe the state of an electron in an atom?

Which principle explains the stability of the electron in an atom, preventing it from falling into the nucleus?

In special relativity, what happens to the kinetic energy of an object as its speed approaches the speed of light?

In the context of special relativity, what happens to the observed frequency of light from a source moving away from the observer at a significant fraction of the speed of light?

Which of the following best describes the concept of 'proper time' in special relativity?

What is the effect of relativistic speeds on the observed color of a star moving rapidly towards the Earth?

When using a lock-in amplifier in a signal detection setup, what is the primary advantage of this technique?

In a laser cooling experiment, what is the primary mechanism for reducing the temperature of atoms?

In a cryogenic experiment, which material is typically used as a coolant to achieve temperatures close to absolute zero?

What is the main purpose of a Faraday cage in an experimental setup?

What is the primary outcome of the "Klein paradox" in quantum mechanics?

What phenomenon does the "Casimir effect" demonstrate?

In quantum mechanics, what is the significance of the "Pauli exclusion principle"?

In the context of nuclear physics, what does the term "magic number" refer to?

What does the Chandrasekhar limit signify in astrophysics?

What is the primary characteristic of a particle in a "superfluid" state?