Acceleration Flashcards
(19 cards)
What is acceleration?
The rate of change of velocity
Acceleration occurs when an object changes its speed or direction.
How is acceleration calculated?
change in velocity = acceleration x time taken
The formula is (v − u) = a x t, where v is final velocity, u is initial velocity, a is acceleration, and t is time.
What does a velocity-time graph show?
How an object’s velocity changes as time passes
The gradient indicates acceleration, and the area under the graph represents displacement.
What is the relationship between final speed, initial speed, acceleration, and distance moved?
(final speed)² - (initial speed)² = (2 × acceleration × distance moved)
This can be expressed as v² - u² = (2 × a × s).
What are the two types of forces?
Contact forces and non-contact forces
Examples include gravitational forces and electrostatic forces.
What is inertia?
The tendency of objects to not change how they are moving unless acted on by a resultant force
Inertia is a property of mass.
What is the formula for calculating resultant force?
resultant force = mass × acceleration
This is also known as Newton’s Second Law: F = m × a.
What is inertial mass?
A measure of how difficult it is to change the velocity of an object
Inertial mass is determined using Newton’s Second Law.
What is the formula for weight?
weight = mass × gravitational field strength
This can be expressed as W = m × g.
What are the components of stopping distance?
Thinking distance and braking distance
Factors affecting stopping distance include speed, mass, friction, brake condition, and reaction time.
What factors can increase a vehicle’s stopping distance?
- Higher speed
- Greater mass
- Low friction
- Worn brakes
- Longer driver reaction time
Typical reaction times range from 0.2s to 0.9s.
What happens to energy when brakes are applied in a vehicle?
Work done by friction transfers energy from the kinetic store to the thermal store of the brakes
The brakes heat up as a result.
What is drag?
A force experienced by an object moving through a fluid
Drag increases with speed until it balances the force causing acceleration.
What is terminal velocity?
Constant velocity reached when drag balances the force causing acceleration
At terminal velocity, the resultant force is zero.
What is the approximate acceleration of a falling object near the Earth’s surface?
About 9.8 m/s²
This acceleration occurs due to the object’s weight.
What is a free body diagram?
A diagram showing the size and direction of forces acting on an object
It helps visualize the net forces involved.
How can two components have the same effect as a single force?
A single force can be resolved into two components acting at right angles to each other.
Fill in the blank: An object that is slowing down is said to be _______.
decelerating
Deceleration is a form of acceleration that indicates a decrease in speed.
What does it mean when an object is in equilibrium?
There is no resultant force acting on the object
In equilibrium, an object maintains a constant velocity.
