P1 Motions, forces and energy Flashcards
What is used to measure length?
Rulers
Rulers are commonly used for measuring straight lengths in various contexts.
What is the formula for speed?
Speed = Distance traveled per unit time
Speed indicates how quickly an object moves over a distance.
Define velocity.
Speed in a given direction
Velocity is a vector quantity, meaning it has both magnitude and direction.
What does a flat line on a distance-time graph indicate?
Object at rest
A flat line shows no change in distance over time.
What does a sloped line on a distance-time graph represent?
Constant speed
The slope indicates a steady rate of distance change over time.
What is acceleration?
Change in velocity per unit time
Acceleration measures how quickly an object speeds up or slows down.
What is the definition of mass?
Measure of matter in an object
Mass is a scalar quantity and does not change with location.
What is weight?
Gravitational force acting on a mass
Weight varies depending on the gravitational field strength.
What is the gravitational field strength (g) near Earth’s surface?
9.8 N/kg
This value is used for calculating weight from mass on Earth.
Define density.
Mass per unit volume
Density is a key property for identifying materials and understanding buoyancy.
What happens to objects with lower density than the fluid?
They float
This principle is crucial for understanding buoyancy and flotation.
What can forces do to an object?
Alter shape, size, or movement
Forces are fundamental to understanding motion and equilibrium.
What is the resultant force?
Sum of all forces acting in a straight line
The resultant force determines the overall effect on an object’s motion.
State Newton’s Second Law.
Force and acceleration are in the same direction
This law illustrates the relationship between force, mass, and acceleration.
What is friction?
Acts between surfaces; can cause heating
Friction opposes motion and can convert kinetic energy into thermal energy.
What does Hooke’s Law state?
Force is proportional to extension up to the limit of proportionality
This law applies to elastic materials and describes their behavior under stretching.
What is the formula for the moment of a force?
Moment = Force × Perpendicular distance from pivot
Moment is a measure of the turning effect of a force.
What is equilibrium?
No resultant force or moment
In equilibrium, an object remains at rest or moves at constant velocity.
Define power in the context of energy.
Rate of energy transfer
Power indicates how quickly work is done or energy is converted.
What is efficiency?
Percentage of useful energy or power output
Efficiency measures how effectively energy is converted to useful work.
What does pressure depend on?
Force and area
Pressure is defined as the amount of force applied over a given area.
How does pressure change in liquids?
Pressure increases with depth
This principle is essential for understanding hydrostatics.
What affects gas pressure?
Volume and temperature
Gas laws describe how pressure varies with changes in volume and temperature.
