Topic 1 Key Concepts in Physics Flashcards
What is a scalar quantity?
A scalar quantity has only magnitude (size) and no direction. Examples include mass, temperature, and time.
What is a vector quantity?
A vector quantity has both magnitude and direction. Examples include displacement, velocity, and force.
What is the difference between distance and displacement?
Distance is a scalar quantity that measures how far an object has travelled, while displacement is a vector quantity that measures the change in position from the starting point, with direction.
Define speed.
Speed is the rate at which an object covers distance. It is a scalar quantity and measured in meters per second (m/s).
Define velocity.
Velocity is the speed of an object in a specific direction. It is a vector quantity and measured in meters per second (m/s).
How do you calculate average speed?
Average speed = Total distance / Total time
What is acceleration?
Acceleration is the rate of change of velocity. It is a vector quantity and measured in meters per second squared (m/s²).
What is the equation for acceleration?
Acceleration = (Final velocity - Initial velocity) / Time
What are the SI units for force, mass, and acceleration?
Force: Newtons (N)
Mass: Kilograms (kg)
Acceleration: Meters per second squared (m/s²)
What is Newton’s First Law of Motion?
An object will remain at rest or in uniform motion in a straight line unless acted upon by a resultant external force.
What is Newton’s Second Law of Motion?
The acceleration of an object is directly proportional to the resultant force acting on it and inversely proportional to its mass.
F = ma
What is Newton’s Third Law of Motion?
For every action, there is an equal and opposite reaction.
Define weight.
Weight is the force exerted by gravity on an object. It is calculated using the equation W=mg, where g is the gravitational field strength.
What is the difference between mass and weight?
Mass is the amount of matter in an object (measured in kg) and does not change with location. Weight is the force of gravity acting on the mass (measured in N) and depends on the gravitational field strength.
What is resultant force?
The resultant force is the single force that has the same effect as all the forces acting on an object combined. It determines whether an object will accelerate, decelerate, or remain at constant velocity.
