Forces P2

Question 1

give examples of scalar quantities

Answer 1

speed, distance, mass, time, volume, density(only has magnitude)

Question 2

give examples of vector quantities

Answer 2

velocity, displacement, force, acceleration, momentum, weight (has magnitude and direction)

Question 3

formula for speed, distance, and time

Answer 3

speed = distance/time

Question 4

what is acceleration

Answer 4

the rate of change of velocity

Question 5

what is the equation to calculate acceleration (m/s^2)

Answer 5

change in velocity (m/s)/time(s)

Question 6

how do you calculate distance or velocity for uniform acceleration

Answer 6

v^2 - u^2 =2 x a x d

Question 7

what is non-uniform motion

Answer 7

motion that is changing

Question 8

how can you investigate the relation between distance, speed, and acceleration

Answer 8

motion of a trolley on a ramp

Question 9

how do you find the gradient of a straight line

Answer 9

change in y/change in x

Question 10

what is speed equal to in a distance time graph

Answer 10

gradient

Question 11

acceleration of an object in a velocity time graph (and gradient)

Answer 11

rise/run

Question 12

what does the area under a velocity time graph represent

Answer 12

displacement (distance travelled)

Question 13

how do you calculate the area under a graph if a triangle is formed

Answer 13

1/2 x base x height

Question 14

how do you find the change in velocity

Answer 14

final velocity - initial velocity

Question 15

if an object starts from rest what is the initial speed

Answer 15

0m/s

Question 16

define kinetic energy/store

Answer 16

the energy an object has as a result of its mass and speed

Question 17

equation for kinetic energy

Answer 17

1/2 x m x v^2

Question 18

define what a force is

Answer 18

a push or a pull that acts on an object due to the interaction with another object

Question 19

what can forces change

Answer 19

speed, direction, shape

Question 20

give 8 examples of forces

Answer 20

weight, electrostatic force, thrust, air resistance, upthrust, compression, tension, reaction force

Question 21

what is a contact force

Answer 21

a force which acts between objects that are physically touching e.g. friction, air resistance, tension, normal force

Question 22

define a non-contact force

Answer 22

a force which acts at a distance, without any contact between bodies, due to the action of a field e.g. gravitational attraction, electrostatic force, magnetic force

Question 23

what is a force pair

Answer 23

when there is an interaction between two objects, a force is exerted on each object

Question 24

what forces are there in a car

Answer 24

thrust, friction, weight, normal force

Question 25

what is 'resolving' a force

Answer 25

how any force vector can be split into two components

Question 26

how do you find the resultant force

Answer 26

by adding together two force vectors

Question 27

when is a system in equilibrium

Answer 27

when all the forces are balanced not equal

Question 28

when three forces act on a body in equilibrium what happens

Answer 28

they can be added together to form a closed vector triangle, resultant force is 0

Question 29

explain why motion in a circle involves constant speed but changing velocity

Answer 29

velocity is a vector quantity, the velocity changes because of this objects in circular motion are always accelerating

Question 30

what is a non-zero resultant force

Answer 30

the forces are unbalanced