Physics concepts, explained
- What causes the Doppler effect?
The Doppler effect is caused by relative motion between a wave source and an observer, causing wavefronts to bunch up or spread out.
- How do you use Snell's law?
Learn how to use Snell's law to calculate the bending of light as it travels between different materials, with step-by-step examples and common pitfalls.
- What is the difference between frequency and wavelength?
Frequency measures how often a wave passes a point, while wavelength measures the physical distance between two consecutive wave peaks.
- What is Coulomb's law?
Coulomb's law calculates the electrical force between two stationary charges, showing it depends on charge size and distance.
- How do you use Kirchhoff's laws?
Learn how to apply Kirchhoff's Current and Voltage laws to solve complex electrical circuits using simple analogies and step-by-step methods.
- What is the difference between voltage, current and resistance?
Voltage is the push, current is the flow, and resistance is the friction in an electrical circuit, all related by Ohm's Law.
- What is impulse?
Impulse is the change in momentum of an object, calculated by multiplying the average force applied to it by the time over which the force acts.
- How do series and parallel circuits differ?
Series circuits have a single path for electric current, while parallel circuits branch into multiple paths, affecting voltage and resistance differently.
- How do you solve a problem with springs and energy?
Learn how to solve physics problems involving springs using the conservation of energy and elastic potential energy.
- What is the work-energy theorem?
The work-energy theorem states that the net work done on an object equals its change in kinetic energy, connecting forces and distance to speed.
- How do you use conservation of momentum?
Learn how to set up and solve physics problems using the law of conservation of momentum for collisions and explosions.
- What is the difference between an elastic and inelastic collision?
An elastic collision conserves both momentum and kinetic energy, while an inelastic collision conserves momentum but loses kinetic energy.
- How does friction work in an inclined plane problem?
Learn how friction opposes motion on an inclined plane and how to calculate it using gravity, normal force, and the angle of the incline.
- What is the difference between kinetic and potential energy?
Kinetic energy is the energy an object has due to its motion, while potential energy is the energy it stores due to its position or state.
- When is mechanical energy conserved?
Mechanical energy is conserved when only conservative forces, like gravity or spring forces, do work on an object or a system.
- What is Newton's third law really saying?
Newton's third law states that forces always occur in equal and opposite pairs between two interacting objects.
- What is the normal force and why is it not always equal to weight?
The normal force is a contact force exerted by a surface to prevent solid objects from passing through each other, and it changes based on applied forces.
- How do you draw a free-body diagram?
A free-body diagram isolates an object and uses arrows to represent external forces, making complex physics problems easier to solve.
- How do you solve a projectile motion problem?
Learn how to solve projectile motion problems by splitting the motion into independent horizontal and vertical parts using standard kinematic equations.
- How do you pick the right kinematics equation?
Learn how to easily choose the right kinematics equation by identifying your known and unknown variables to find the perfect match.
- What does a velocity-time graph tell you?
A velocity-time graph shows how an object's speed and direction change over time, where the slope is acceleration and the area is displacement.
- What is the difference between speed and velocity?
Speed measures how fast an object moves, while velocity is a vector quantity that includes both speed and the direction of motion.