Topic 1: Motion, forces and energy Flashcards
(26 cards)
How do you find length or volume using rulers and measuring cylinders?
Use a ruler to measure the length of an object, and use a measuring cylinder to determine the volume of liquids or irregular solids by displacement.
How can time intervals be measured using clocks and digital timers?
Time intervals are measured by recording the start and end times using a clock or digital timer and subtracting the start time from the end time.
How do you determine an average value for a small distance or short time interval?
Measure the distance or time multiple times, then calculate the average by dividing the total distance by the total time.
What is a scalar quantity?
A scalar quantity has magnitude only, with no direction (e.g., distance, speed, time, mass, energy, temperature).
What is a vector quantity?
A vector quantity has both magnitude and direction (e.g., force, weight, velocity, acceleration, gravitational field strength).
What is the equation for speed?
Speed = Distance / Time (v = s/t).
What is the equation for average speed?
Average Speed = Total Distance / Total Time.
How do you define velocity?
Velocity is speed in a given direction.
What is acceleration?
Acceleration is the change in velocity per unit time (a = Δv / Δt).
How do you calculate speed from a distance–time graph?
Speed is the gradient (slope) of the straight-line section of the distance–time graph.
How do you calculate acceleration from a speed–time graph?
Acceleration is the gradient (slope) of the straight-line section of the speed–time graph.
What is the equation for gravitational field strength (g)?
Gravitational Field Strength (g) = Weight (W) / Mass (m).
What is the equation for density?
Density (ρ) = Mass (m) / Volume (V).
How is the density of a liquid, solid, or irregular object determined?
Measure mass and volume (e.g., by water displacement for irregular solids) and calculate density using the equation ρ = m / V.
What is friction?
Friction is the force between two surfaces that may impede motion and produce heating.
What is the equation for force?
Force (F) = Mass (m) × Acceleration (a), or F = ma.
What is a moment of a force?
The moment is the turning effect of a force, calculated as moment = force × perpendicular distance from the pivot.
What is the principle of moments?
The principle of moments states that when an object is in equilibrium, the sum of the moments on one side of the pivot equals the sum on the other side.
What is the centre of gravity?
The centre of gravity is the point where an object’s mass can be considered to be concentrated, and it affects the object’s stability.
What is the equation for kinetic energy?
Kinetic Energy (Ek) = 1/2 × Mass (m) × Velocity² (v²).
What is the equation for gravitational potential energy?
Gravitational Potential Energy (ΔEp) = Mass (m) × Gravitational Field Strength (g) × Height (Δh).
What is mechanical work?
Mechanical work is the energy transferred by a force acting over a distance, calculated as Work (W) = Force (F) × Distance (d).
What is power?
Power is the rate of doing work or transferring energy, calculated as Power (P) = Work (W) / Time (t).
What is efficiency?
Efficiency is the ratio of useful energy output to total energy input, expressed as Efficiency = (Useful Energy Output / Total Energy Input) × 100%.
