CP1- Motion

Question 1

what is a vector? give examples.

Answer 1

• has both size and direction
• force, velocity, displacement, weight, acceleration, momentum

Question 2

what is a scalar? give examples.

Answer 2

• do not have direction, only magnitude
• speed, distance, mass, energy

Question 3

what is the difference between velocity and speed?

Answer 3

• velocity is a vector and is speed in a particular direction whereas speed is a scalar
• two vehicles travelling in opposite directions may have the same speed however they will not have the same velocity since they are not travelling in the same direction

Question 4

what is the difference between displacement and distance?

Answer 4

• distance is a scalar whereas displacement is a vector
• distance is how far an object has moved, not involving direction
• displacement measures the distance and direction from a starting point to an ending point in a straight line rather than the entire journey

Question 5

what is acceleration?

Answer 5

The change in velocity in a certain amount of time.

Question 6

what is momentum?

Answer 6

a combination of mass and velocity.

Question 7

what does it mean if an object is travelling at a constant speed with changing velocity?

Answer 7

an object is changing direction all while remaining at the same speed.

Question 8

what is the equation for speed?

Answer 8

speed = distance/time

sad beautiful tragic: distance, timing breakdown, fighting, SILENCE the train runs off its tracks…

Question 9

what is the instantaneous speed?

Answer 9

the speed at a particular point in a journey.

Question 10

what is the average walking speed?

Answer 10

1.4 m/s

Question 11

what do horizontal lines mean on a distance-time graph?

Answer 11

the object is stationary.

Question 12

how do you calculate the speed from a distance-time graph?

Answer 12

• the speed is calculated from the gradient of line
• if the line is curved you have to draw the tangent first

Question 13

what do curves represent on a distance-time graph?

Answer 13

acceleration or decelerating.

Question 14

what are the units of acceleration?

Answer 14

m/s^2

Question 15

how do you work out the average acceleration?

Answer 15

acceleration= change in velocity / time

a= (final velocity-initial velocity) / time

Question 16

what is uniform acceleration?

Answer 16

constant acceleration which does not speed up, slow down or change direction. eg. an object falling will remain constant and uniform due to gravity

Question 17

what is the different between uniform acceleration and average acceleration?

Answer 17

average acceleration accounts for changes over time whereas uniform acceleration does not change direction or magnitude.

Question 18

what is the equation for uniform acceleration?

Answer 18

v^2 - u^2 = 2 x acceleration x distance

Question 19

what is the acceleration due to gravity where there are no other forces interfering?

Answer 19

9.8 m/s^2 or 10m/s^2

Question 20

what does a horizontal line mean on a velocity-time graph?

Answer 20

the object is travelling at a constant speed

Question 21

what does a sloping line mean on a velocity-time graph?

Answer 21

shows that the object is accelerating or decelerating , steeper= more acceleration or deceleration

Question 22

how do you find the acceleration on a velocity-time graph?

Answer 22

• find the gradient of a line, or the tangent
• this is because acceleration= change in velocity / time

Question 23

what does a straight line (going down or up) on a velocity-time graph mean?

Answer 23

constant acceleration/deceleration

Question 24

how do you calculate distance from a velocity-time graph?

Answer 24

• calculate the area under sections of the graph
• you can split the graph into squares and triangles

Question 25

What does a steeper graph mean on a distance time graph?

Answer 25

A steeper graph means it’s going faster

Question 26

What does a steeper graph mean on a velocity time graph?

Answer 26

A steeper graph means the greater the acceleration or deceleration