Motion - Equations and Graphs

Question 1

what is a scalar?

Answer 1

a quantity which is fully described by its magnitude

Question 2

examples of scalar quantities

Answer 2

distance, speed, mass

Question 3

what is a vector?

Answer 3

a quantity which requires magnitude and direction

Question 4

examples of vector quantities

Answer 4

acceleration, force, velocity, displacement

Question 5

what are the 4 equations of motion?

Answer 5

1. v=u+at
2. s=ut+1/2at^2
3. v^2=u^2+2as
4. s=1/2(u+v)t

Question 6

what does each letter of SUVAT stand for and what are their units?

Answer 6

S displacement m
U initial velocity ms-1
V final velocity ms-1
A acceleration ms-2
T time s

Question 7

what is the gradient of a velocity time graph?

Answer 7

acceleration

Question 8

what is the area under a velocity time graph?

Answer 8

displacement

Question 9

what is the gradient of a displacement time graph?

Answer 9

velocity

Question 10

definition of acceleration

Answer 10

the rate of change of velocity

Question 11

definition of displacement

Answer 11

how far an object is from its start point

Question 12

definition of velocity

Answer 12

the rate of change of displacement

Question 13

what do the a-t and s-t graphs look like for an object moving at a constant velocity?

Answer 13

a-t acceleration is zero (-)

s-t displacement increases at a constant rate (/)

Question 14

what do the a-t and s-t graphs look like for an object moving with constant increasing velocity?

Answer 14

a-t acceleration is constant and positive (above x-axis)

s-t displacement increases by a greater amount each second (gradient increasing)

Question 15

what do the a-t and s-t graphs look like for an object moving with constant decreasing velocity?

Answer 15

a-t acceleration is constant and negative (below x-axis)

s-t gradient decreases over time

Question 16

velocity-time graph of an object thrown vertically upwards then falling back to Earth.

Answer 16

gradient is a constant negative value (-9.8ms-2)
total area under the graph is zero
velocity is 0ms-1 at max height

Question 17

velocity-time graph of a bouncing ball

Answer 17

slope of the line for the majority of the graph is a constant negative value (always acceleration downwards whether motion is up or down)
nearly a vertical line represent motion of the ball when in contact with the ground and rebounding
area under graph reduces with each bounce as displacement reduces.

Question 18

acceleration-time graph of an object thrown vertically upwards then falling back to Earth.

Answer 18

horizontal line under x-axis (-9.8ms-2)

Question 19

displacement-time graph of an object thrown vertically upwards then falling back to Earth.

Answer 19

decreasing gradient until max height then increasing gradient back down to x-axis (n shape)