Mechanics (Motion)

Question 1

Define a Scalar Quantity

Answer 1

Quantity with only magnitude

Question 2

Define a Vector Quantity

Answer 2

Quantity with a magnitude and direction

Question 3

What is Distance

Answer 3

• Measured in Meters (m)
• distance of two points along a certain path
• Scalar quantity

Question 4

What is Displacement

Answer 4

• Measured in Meters (m)
• difference in the position of two points
• Vector quantity

Question 5

What is Speed

Answer 5

• ms^-1
• Change in DISTANCE over time
• Scalar quantity

Question 6

What is Velocity

Answer 6

• ms^-1
• Change in DISPLACEMENT over time
• Vector quantity

Question 7

What does the GRADIENT of a DISPLACEMENT/TIME graph give you?

Answer 7

VELOCITY

Question 8

What does the GRADIENT of a VELOCITY/TIME graph give you?

Answer 8

ACCELERATION

Question 9

What does the AREA UNDER THE CURVE of a VELOCITY/TIME graph give you?

Answer 9

DISPLACEMENT

Question 10

What does the AREA UNDER THE CURVE of an ACCELERATION/TIME graph?

Answer 10

VELOCITY

Question 11

What is the AVERAGE VALUE in a graph describing motion?

Answer 11

Average value of the entire motion

* Calculated using the final and initial values

Question 12

What is the INSTANTANEOUS VALUE in a graph describing motion?

Answer 12

the value at a particular moment in time

* Calculated using two consecutive values

Question 13

What is Acceleration

Answer 13

• ms^-2
• Change in VELOCITY over time
• Vector quantity

Question 14

Define a Projectile

Answer 14

an object which only has gravity as an acting force. (aside from air resistance)

Question 15

Horizontal movement of a Projectile

Answer 15

• No forces acting on it
• Velocity is constant
• No Acceleration

Question 16

Vertical movement of a Projectile

Answer 16

• Gravity acting on it
• Velocity is changing
• Constant Acceleration (9.8ms^-1)

Question 17

What is the nature of Projectile Motion

Answer 17

• Projectile moves horizontally and vertically

* These components move INDEPENDENTLY from each other

Question 18

Describe the effects of Fluid resistance on Projectile Motion

Answer 18

• when an object moves through a fluid, there will be a fluid resistance that generates friction.
• This causes “drag” and will slow the object’s trajectory
• Force of drag is ALWAYS opposite to the direction of the movement

EFFECTS:

• Trajectory BEGINS the same
• Max height of projectile is lower
• Horizontal distance is smaller
• Trajectory no longer symmetrical

Question 19

What happens at “Terminal Velocity”?

Answer 19

• Air resistance counteracts the force of gravity

* Acceleration is ZERO