P2 topic 3

Question 1

what does the acceleration of an object depend on?

Answer 1

size of resultant force, mass of object

Question 2

when is the acceleration of an object larger?

Answer 2

when resultant force is greater and mass is smaller

Question 3

Newton’s second law

Answer 3

shows the link between force and mass, using the equation F=ma

Question 4

what will happen if there is a resultant force?

Answer 4

an object will have an acceleration

Question 5

how can you investigate the link between resultant force, mass and acceleration?

Answer 5

by using trolleys and a motion sensor connected to a computer

Question 6

how do you investigate the relationship between force and acceleration?

Answer 6

keep the mass of the trolley constant

Question 7

how do you investigate the relationship between acceleration and mass?

Answer 7

keep force on trolley constant

Question 8

mass of an object

Answer 8

the amount of matter it contains- mass of an object remains constant and is a scalar property

Question 9

weight of an object

Answer 9

the Earth’s gravitational force acting on it- it’s measured in newtons. the weight of an object depends where it is- weight is a vector quantity

Question 10

what weight does an object of 1kg have on earth?

Answer 10

9.8N or 10N

Question 11

what is the earth’a gravitational field strength?

Answer 11

10N/Kg

Question 12

what do all falling objects have?

Answer 12

the sane acceleration of free fall, 9.8 m/s2 (about 10), have an acceleration that is independent of their mass

Question 13

how do objects fall in a vacuum?

Answer 13

they all fall at the same rate

Question 14

what do all objects moving in air experience?

Answer 14

air resistance

Question 15

what does the drag on an object depend on?

Answer 15

it depends on its speed drag increased as spied increases), shape and area

Question 16

terminal velocity

Answer 16

the constant velocity of a falling object when the net force acting on it is zero

Question 17

how does an object get to terminal velocity?

Answer 17

air resistance increases as speed increases, until air resistance is equal to the weight of an object- at this point, the resultant force on the object is zero

Question 18

force

Answer 18

a push or pull exerted by one object on another- it’s a vector quantity

Question 19

vector

Answer 19

a quantity that has both magnitude and direction

Question 20

what must be taken into account when adding forces?

Answer 20

their direction

Question 21

free-body force diagram

Answer 21

a diagram showing all the forces acting on an object

Question 22

Newton’s first law of motion

Answer 22

States that if there is no resultant force acting on an object then if stationary the object will remain at rest and if moving, the object will keep moving at a constant speed in a straight line

Question 23

Newton’s third law of motion

Answer 23

when two objects interact, each object exerts an equal but opposite force on the other

Question 24

what do we call these equal and opposite forces?

Answer 24

reaction forces

Question 25

what forces does a car travelling down a straight road at a constant velocity have acting on it?

Answer 25

the total forward force between the tyres and the road; frictional forces between the tyres and the road; the weight of the car; the total upward contact force provided by the road

Question 26

action at a distance

Answer 26

the gravitational force between the interacting Sun and the Earth acts over a long distance

Question 27

What does Newton's third law state about the sun and the earth?

Answer 27

the force provided by the Sun on the Earth is equal in size but opposite in direction to the force provided by the Earth on the Sun

Question 28

weight

Answer 28

the gravitational force acting on an object in the Earth- every object has weight

Question 29

what does the earth do?

Answer 29

interacts with every object on it, including us- we are pulling the earth towards us with a force equal to our weight

Question 30

what is another name for air resistance?

Answer 30

drag

Question 31

what is the gradient of a distance-time graph equal to?

Answer 31

the speed of the object

Question 32

what is the gradient of a velocity time graph equal to?

Answer 32

acceleration of an object

Question 33

what is the area under a velocity time graph equal to?

Answer 33

distance travelled by the object

Question 34

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

Answer 34

it shows constant acceleration/velocity, whilst on a distance-time graph it shows that the object is stationary

Question 35

scalar quantity

Answer 35

only has magnitude e.g distance, mass, volume, temperature, speed and energy

Question 36

vector quantity

Answer 36

has both magnitude and direction e.g displacement, velocity, acceleration and force

Question 37

displacement

Answer 37

has a size that is equal to the distance from a specified point-it also has a direction

Question 38

speed

Answer 38

the rate of change of distance-how fast an object travels

Question 39

velocity

Answer 39

its speed in a specified direction- the rate of change of displacement

Question 40

acceleration

Answer 40

the rate of change of velocity of an object- if the velocity of an object increases or decreases or its direction is changing, it's accelerating

Question 41

deceleration

Answer 41

slowing down- negative acceleration. an object whose velocity decreases with time is said to have deceleration

Question 42

Ohm's law

Answer 42

the current flowing through a resistor at a constant temp is directly proportional to the potential difference across it