Chapter 2: Describing Motion

Question 1

Speed

Answer 1

The distance travelled by an object per unit time
The rate of change of position of an object in any direction

Question 2

Average Speed

Answer 2

The speed is calculated from the total distance travelled divided by the total time taken

Question 3

Average Speed Formula

Answer 3

total distance travelled/ total time taken.

Question 4

light gates

Answer 4

allow the speed of an object passing between them to be calculated electronically.

Question 5

interrupt card

Answer 5

allows the speed of an object passing through a light gate to be calculated; a timer starts when the card breaks the beam and stops when the bam is no longer broken.

Question 6

light gate experiment (4)

Answer 6

• Connect two light gates to an electronic timer or a computer.
• Each light gate has a beam of invisible infrared radiation.
• The peg attached to the trolley breaks the beam of one light gate to start the timer and breaks the second beam to stop the timer.
  -The timer them shows the time taken to travel the distance between the two light gates.

Question 7

light gate experiment pt 2 (4)

Answer 7

-A piece of card called the interrupt card is mounted on the trolley.
-As the trolley passes through the gate, the leading edge of the interrupt card breaks the beam to start the timer.
-When the trailing edge passes the gate the beam is no longer broken and the timer stops.
-The faster the trolley is moving the shorter the timer for which the beam is broken.

Question 8

Speed formula

Answer 8

Distance / Time

Question 9

SI units for
Distance
Time
Speed

Answer 9

meter or kilometre
second or hour
meters per second or kilometres per hour

Question 10

Acceleration

Answer 10

-The rate of change of the velocity of an object
-Acceleration is a vector quantity that is defined as the rate at which an object changes its velocity.
-The rate of change in velocity in a given time.

Question 11

Velocity

Answer 11

the speed of an object in a stated direction

Question 12

Vector

Answer 12

has both magnitude (size) and direction/

Question 13

Scalar

Answer 13

is something that has magnitude but no direction.

Question 14

To calculate the Velocity

Answer 14

Final Distance (Position) - Initial Distance then divided by time

Question 15

To calculate the Displacement

Answer 15

Displacement = Final position – initial position = change in position

Question 16

To calculate the Acceleration

Answer 16

To calculate the Acceleration

Question 17

Displacement

Answer 17

Change in position, Distance travelled.

Question 18

Acceleration Formula

Answer 18

change in velocity/ time taken
a = v - u/ t

Question 19

great acceleration

Answer 19

Steeper the slope

Question 20

negative slope shows

Answer 20

deceleration on the graph

Question 21

Final velocity equation

Answer 21

v = u + at

Question 22

Final velocity 2 Equation

Answer 22

v2 = u2 + 2as

Question 23

displacement equation

Answer 23

ut + 0.5at2
ut + at2/2

Question 24

displacement eqaution

Answer 24

(u+v)t / 2