Flashcards in Topic 2.1 Kinematics Deck (11):

1

## Define displacement

### o Displacement: The distance travelled in a particular direction from a specified origin. A vector.

2

## Define velocity

### o Velocity: The rate of change of displacement with time. A vector. Unit: ms-1

3

## Define speed

### o Speed and Distance: The scalar versions of velocity and displacement.

4

## Define acceleration

### o Acceleration: The rate of change of velocity with time. A vector. Unit ms-2

5

## • 2.1.2: Explain the difference between instantaneous and average values of speed, velocity and acceleration

### o Instantaneous: The value of a quantity measured at an instant in time, as opposed to an average quantity measured over a period of time.

6

## • 2.1.4: Identify the acceleration of a body falling in a vacuum near the Earth’s surface with the acceleration g or free fall

### o Acceleration Due to Gravity: Ignoring air resistance, a free-falling object accelerates at the surface of the Earth at approx. 9.8ms-2 This is numerically equal to gravitational field strength.

7

## • 2.1.6: Describe the effects of air resistance on falling objects

### o Terminal Velocity: Air resistance is proportional to speed, so an accelerating object will achieve terminal velocity

8

## Calculate and interpret the gradients of displacement-time graphs

### o DISPLACEMENT-TIME GRAPHS: Gradient is velocity.

9

## Calculate and interpret the gradients and area under the curve of velocity-time graphs

### o VELOCITY-TIME GRAPHS: Gradient is acceleration. Area under graph is displacement.

10

## Calculate and interpret the area under the curve of acceleration-time graphs

### o ACCELERATION-TIME GRAPHS: Area under graph is change in velocity.

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