Physics Test 3
What is velocity?
Velocity is speed in a given direction (a vector quantity).
What is the difference between speed and velocity?
Speed is scalar (no direction); velocity is vector (includes direction).
What are the units for acceleration?
Metres per second squared (m/s²)
What does a flat line on a distance-time graph mean?
The object is stationary.
What does a straight, sloped line on a distance-time graph show?
Constant speed.
How do you find speed from a distance-time graph?
Speed = Gradient of the line
What does a curved line on a distance-time graph represent?
Changing speed (acceleration or deceleration)
What does a flat line on a velocity-time graph indicate?
Constant velocity.
What does a sloped line on a velocity-time graph indicate?
Acceleration (positive or negative depending on direction of slope)
How do you find acceleration from a velocity-time graph?
Acceleration = Gradient of the line
How do you find distance travelled from a velocity-time graph?
Distance = Area under the graph
Can an object be accelerating if its speed is constant?
Yes, if it is changing direction (e.g. moving in a circle)
What is a force?
A push or pull acting on an object due to interaction with another object.
What is a balanced force?
When the forces acting on an object are equal in size and opposite in direction, resulting in no change in motion.
What is an unbalanced force?
When forces acting on an object are not equal, causing a change in motion.
What is Newton’s First Law of Motion?
An object remains at rest or in uniform motion unless acted upon by an unbalanced force.
What is the resultant force?
The single force that has the same effect as all the forces acting on an object combined.
What happens to an object if the resultant force is zero?
It stays still or continues to move at a constant velocity.
What is the difference between mass and weight?
Mass is the amount of matter (kg), weight is the force due to gravity (N).
What are contact forces?
Forces that occur when two objects are physically touching (e.g. friction, tension, normal contact force).
What are non-contact forces?
Forces that act at a distance (e.g. gravity, magnetic, electrostatic).
What is tension?
The pulling force transmitted through a string, rope, or cable.