[Part 2]- P9- motion 🚲

Question 1

What’s a distance time graph ?

Hint: represent the motion

Answer 1

• a distance-time graph, shows how far an object has travelled in a given time
• ; they also represent the motion of an object.

Question 2

How do distance-time graphs, represent the motion of an object ?

Hint: axis

Answer 2

• distance time graphs can represent the motion of an object because:
• the y-axis represents the distance travelled by the object.
• and the x-axis, represents the time taken for the object to travel this distance.

Question 3

Fill in the gaps: If an object moves along a _______ line, then the ________ traveled by the object, can be represented by a ________-time graph.

Answer 3

• If an object moves along a straight line, then the distance traveled by the object, can be represented by a distance-time graph.

Question 4

What’s the slope or gradient of a distance-time graph, equal to ?

Answer 4

• the slope or gradient of a distance-time graph, is equal to the speed

Question 5

What’s the equation, to work out the gradient, that links the distance travelled and time taken ?

Answer 5

• gradient= distance travelled/ time taken

Question 6

What’s a gradient [of a straight-line graph] ?

Hint: change of the quantity

Answer 6

• a gradient, is a change of the quantity plotted on the y-axis, divided by the change of the quantity plotted on the x-axis

Question 7

What’s a tangent ?

Hint: touch a point on a curve- why ?

Answer 7

• a tangent, is a straight line drawn, to touch a point on a curve, so it has the same gradient as the curve at that point.

Question 8

In a distance-time graph, what does an upward sloping curve, tell us about the speed, of an object

Answer 8

• in a distance-time graph, the upward sloping curve, tell us that the object is constantly increasing in speed [accelerating]

Question 9

In a distance-time graph, what does a straight line, tell us about the speed, of an object ?

Answer 9

• in a distance time graph, a straight line, tells us that the object is moving at a steady and constant speed

Question 10

In a distance-time graph, what does a plateau, tell us about the speed, of an object ?

Answer 10

• in a distance-time graph, a plateau, tells us that the object is stationary and isn’t moving

Question 11

What does average speed mean ?

Hint: total

Answer 11

• average speed is the total distance/time

Question 12

What does instantaneous speed mean ?

Hint: one instant

Answer 12

• instantaneous speed, is speed at one instant in time
• [instantaneous speed is used, when speed isn’t constant. For example, when there’s an acceleration or deceleration]

Question 13

What’s the difference between a tangent 🆚 a gradient ?

Answer 13

• a tangent, is a straight line drawn, to touch a point on a curve, so it has the same gradient as the curve at that point.
• ; a gradient, is a change of the quantity plotted on the y-axis, divided by the change of the quantity plotted on the x-axis

Question 14

What’s the difference between average speed 🆚 instantaneous speed ?

Answer 14

• average speed is the total distance/time
• ; instantaneous speed, is speed at one instant in time
• [instantaneous speed is used, when speed isn’t constant. For example, when there’s an acceleration or deceleration]

Question 15

What’s velocity ?

Answer 15

• velocity, [of an object] is speed in a given direction.
• ; unlike speed it’s a vector quantity because, it has a magnitude [size] and direction.

Question 16

What does speed mean ?

Hint: in a given time

Answer 16

• speed, is the distance an object has travelled, in a given time.
• ; speed is a scalar quantity because, it doesn’t given us any idea, of the direction of a journey. [it only has a magnitude- size]

Question 17

How can velocity be calculated ?

Answer 17

• velocity can be calculated the same way as speed; a direction must be stated.

Question 18

Why does motion in a circle involve constant speed, but a changing velocity ? ⭕️

Hint: constantly changing

Answer 18

• if an object moves at a constant speed in a circle, then it’s velocity is constantly changing [although it’s speed is constant]
• ; this can also include, an object travelling around part of a circle [e.g- moving around a corner]

Question 19

What’s the difference between speed 🆚 velocity ? [4]

Answer 19

• speed, is the distance an object has travelled, in a given time.
• ; speed is a scalar quantity because, it doesn’t given us any idea, of the direction of a journey. [it only has a magnitude- size]
• velocity, [of an object] is speed in a given direction.
• ; unlike speed it’s a vector quantity because, it has a magnitude [size] and direction.