Module 3.1 Flashcards
What is Acceleration?
The rate of change of velocity
What is Average speed?
Distance over time for the entire region of interest.
What is Braking distance?
The distance travelled between the brakes being applied and the vehicle coming to a stop. It is affected by the vehicle and road conditions.
What is Displacement?
The direct distance between an object’s starting and ending positions. It is a vector quantity and so has both a direction and a magnitude.
What is Displacement-Time graphs?
Plots showing how displacement changes over a period of time. The gradient gives the velocity. Curved lines represent an acceleration.
What is Free-fall?
An object is said to be in free fall when the only force acting on it is the force of gravity.
What is Instantaneous Speed?
The exact speed of an object at a specific given point.
What is Projectile motion?
The motion of an object that is fired from a point and then upon which only gravity acts. When solving projectile motion problems , it is useful to split the motion into horizontal and vertical components.
What is Reaction time?
The time taken to process a stimulus and trigger a response to it. It is affected by alcohol, drugs and tiredness.
What is Stopping distance?
The sum of thinking distance and braking distance for a driven vehicle.
What is Thinking distance?
The distance travelled in the time it takes for driver to react. It is affected by alcohol, drugs and tiredness.
What is Velocity-time graphs?
Plots showing how velocity changes over a period of time. The gradient gives acceleration. Curved lines represent changing acceleration.
What is Velocity?
The rate of change of displacement. It is a vector quantity and so has a direction and magnitude.
Describe how the terminal velocity of an object can be determined using light gates.
- Set up the light gates vertically and measure the distance between them.
- Connect them to a data logger and then release an object from rest above them, measuring the time it takes for the object between the two gates.
- Using the time and the known distance, you can calculate the velocity of the falling velocity.
Describe how light gates can also be used to investigate conservation of momentum.
- Place two cats on a linear air track (to reduce friction) with repelling magnets so that they do not stick together.
- Attach a card to the top of each cart so they break the beams of the light gates when they pass.
- Keep one cart stationary and push the other towards it, measuring its velocity before the collision.
- Then measure the velocity of both carts after the collision and calculate the momentum before and after.
