11.1 linear motion

Question 1

define scalar quantity

Answer 1

when measurements are only described in terms of size or magnitude- mass, distance and speed

Question 2

define vector quantity

Answer 2

when measurements are described in terms of magnitude (size) and direction- weight, acceleration, displacement, velocity and momentum

Question 3

define mass

Answer 3

the quantity of matter the body possesses, measured in kg

Question 4

define weight

Answer 4

the force on a given mass due to gravity, measured in newtons

Question 5

equation for weight

Answer 5

weight (newtons)= mass (kg) x gravity (9.8)

Question 6

define distance

Answer 6

measured in metres and is the path a body takes as it moves from the starting position to the finishing position

Question 7

define displacement

Answer 7

measured in metres and is the shortest route in a straight line between the starting and finishing position

Question 8

define speed

Answer 8

a measurement in metres/second of the body’s movement per unit of time with no reference to direction

Question 9

define velocity

Answer 9

measured in metres/second and is the rate of change of displacement

Question 10

equation for speed

Answer 10

distance covered/ time taken

Question 11

equation for velocity

Answer 11

displacement/ time taken

Question 12

define distance-time graph

Answer 12

a type of graph that shows the distance travelled over a period of time

Question 13

how do you calculate gradient

Answer 13

change in the y axis/ change in the x axis

Question 14

what are the three types of graphs of motion?

Answer 14

distance-time graphs, velocity-time graphs and speed-time graphs

Question 15

define acceleration

Answer 15

measured in m/s2 and is the rate of change of velocity

Question 16

how to calculate acceleration

Answer 16

change in velocity/ time

Question 17

how to calculate change in velocity

Answer 17

(final velocity- initial velocity)/ time

Question 18

how to calculate momentum

Answer 18

momentum (kgm/s) = mass (kg) x velocity (m/s)

Question 19

define external force

Answer 19

comes from outside the body

Question 20

define internal force

Answer 20

is generated by the skeletal muscles

Question 21

what are the two vertical forces?

Answer 21

weight and ground reaction force

Question 22

what are the two horizontal forces?

Answer 22

friction and air resistance

Question 23

what factors affect friction?

Answer 23

the surface characteristics of the two bodies in contact, the temperature of the two surfaces in contact and the mass of the objects that are sliding

Question 24

what does air resistance depend upon?

Answer 24

the velocity of the moving body, the cross-sectional area of the moving body and the shape & surface characteristics of a moving body

Question 25

what direction is weight?

Answer 25

downwards

Question 26

what direction is the ground reaction force?

Answer 26

upwards

Question 27

what direction is friction?

Answer 27

direction of motion

Question 28

what direction is air resistance?

Answer 28

opposite direction of motion

Question 29

define net force

Answer 29

the resultant force acting on a body when all forces have been considered

Question 30

equation for impulse

Answer 30

impulse= force x time

Question 31

define net impulse

Answer 31

a combination of positive and negative impulses

Question 32

how is negative impulse showed on force-time graphs?

Answer 32

first, under the x axis

Question 33

how is positive impulse showed on force-time graphs?

Answer 33

second, above x axis