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Flashcards in Forces and Motion Deck (53)
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1

What is the equation for speed?

speed = distance/time

2

What is the equation for weight?

weight = mass x gravity

3

What is the equation for acceleration?

acceleration = change in velocity/time

4

What is the relationship between force, mass, and acceleration?

force = mass x acceleration

5

What does the gradient in a distance time graph represent?

speed

6

What does the gradient in a velocity time graph represent?

acceleration

7

What does a curving line represent on a distance time graph?

acceleration/ deceleration

8

What does a curving line represent on a velocity time graph?

increasing acceleration / deceleration

9

What does a horizontal line represent on a distance time graph?

stopped

10

What does a horizontal line represent on a velocity time graph?

steady speed

11

What IS acceleration?

the rate of increase of velocity with time

12

Why do objects reach terminal velocity?

when an object has the balanced forces of air resistance and weight on it. It falls at a constant speed. The two examples are a sky diver and sycamore seeds.

13

How do you find distance from a velocity time graph?

area under graph

14

What is the unit for velocity?

m/s

15

What is the unit for acceleration?

m/s2

16

What is the unit for force?

Newtons

17

What is the unit for momentum?

kg m/s

18

What is the unit for volume?

m3

19

What is the fancy unit for temperature?

Kelvin (-273°C)

20

What is the difference between a vector and a scalar quantity?

a vector quantity has both direction and magnitude, where as a scalar quantity just has magnitude.

21

What IS friction?

the force which opposes motion

22

Use ideas about molecules to explain how pressure is caused inside an object.

Any three of
MP1. idea of (continuous) random
movement;
MP2. collisions / impact/eq;
MP3. with (inside) walls;
MP4. idea that force is produced (by
bombarding molecules);
MP5. idea of pressure as force on an
area;

23

What is the equation for gravitational potential energy?

gravitational potential energy = mass x gravity x height

24

What is the equation for refractive index?

n = sin i/ sin r

25

What is Newton's third law of motion?

for every action, there is an equal and opposite reaction

26

What does stopping distance consist of?

thinking distance = braking distance

27

What 2 things affect thinking distance?

- speed
- state of driver (eg. old age, tiredness, dugs, alcohol, inexperience?

28

What 4 things affect breaking distance?

- speed
- mass of vehicle
- quality of brakes
- grip (road surface, weather, tyres)

29

What is the equation for momentum?

momentum = mass x velocity

30

What is the unit for momentum?

kg m/s