Phy 1A

Question 1

Speed(ms-1)=

Velocity (ms-1)=

Answer 1

Amount of time taken to move a certain distance
Distance/time

the rate of change of displacement of an object
Displacement/time

Question 2

Acceleration(ms-2)

Average speed

Instantaneous speed

The vector nature of acceleration is very important. One of the consequences is that if an object changes only the direction of its velocity, ….

Answer 2

Total distance of a journey/ total time of a journey

Speed of an object at a particular moment in time which can be found from gradient of tangent to a distance time graph at that time

The vector defined as the Rate of change in velocity
Change in velocity/time taken to change velocity

page 11 last part in white
it is accelerating, while remaining at a constant speed. Similarly, deceleration represents a negative change in velocity, and so could be stated as a negative acceleration.

Question 3

Displacement

Vector vs scalar

Answer 3

The vector measurement of distance in a specific direction

Magnitude and direction VS direction

Question 4

scalar quantities

Answer 4

distance
speed
time
mass
volume
density
energy
electric charge
pressure
tempertaure

Question 5

vector quantities

Answer 5

displacement
velocity
acceleration
force
momentum

Question 6

displacement-time graph

flat line in d/t graph or displacement/t graph means..
,however in velocity time graph…..

A straight (diagonal) slope represents…..
A curved slope represents…..

gradient of d-t graph=

Answer 6

a graph showing positions visited on a journey, with displacement on y-axis and time on the x-axis

…object is not moving
….flat line on zero axis as velocity is unchanging

…..a constant velocity
….. an acceleration

=speed or velocity

Question 7

velocity-time graph

constant velocity=

gradient=

A straight line….
A curved line represents….
a zero slope (horizontal line) represents…

5)distance from v-t graph

(A positive slope represents an increase in velocity in the positive direction and A negative slope represents an increase in velocity in the negative direction)

Answer 7

a graph showing velocities on a journey with velocity on y-axis and time on x-axis

=straight line

=acceleration

….represents uniform acceleration
…..non-uniform acceleration
…..represents motion with constant velocity

5)v=d/t –» d=v x t
so distance traveled is equal to area between graph and x axis

Question 8

acceleration-time graph

A zero slope (horizontal line) represents….
The area under the curve equals..
(The steepness of the slope is meaningless)

Answer 8

graph showing how acceleration changes with time

….an object undergoing constant acceleration
….the change in velocity

Question 9

resultant force

how to find resultant force for non perpendicular vectors?

free body diagram

Answer 9

the total force acting on a body when all the forces are added together accounting for their directions

make parallelogram(forces acting from same origin the mirror it) the diagonal across parallelogram from starting point is the resultant force

diagram showing object isolated and all the forces that act on it are drawn at the points where they act, using arrows to represent the forces

Question 10

moment

equilibrium

sum of clockwise moment=

centre of gravity

Answer 10

the tendency to cause rotation
moment(nm)=force(N) X Perpendicular distance to the line of action of the force

the situation for a body where there is zero resultant force and zero resultant moment. it will have zero acceleration

sum of anticlockwise moments

the point through which the weight of an objects appears to act