Motion

Question 1

what does a stationary object look like in a distant time graph

Answer 1

straight line

Question 2

what does gradient of distance time graph show

Answer 2

speed

Question 3

instantaneous speed

Answer 3

speed of the car over a short interval of time. find by drawing tangent to distance-time graph

Question 4

displacement scalar or vector

Answer 4

vector obviously

Question 5

average velocity

Answer 5

change in displacement/time taken

Question 6

gradient of displacement time graph

Answer 6

velocity

Question 7

acceleration

Answer 7

rate of change of velocity

Question 8

gradient of velocity time graph

Answer 8

acceleration

Question 9

constant acceleration on a vt graph

Answer 9

straight positive gradient line

Question 10

how to calculate displacement from vt graph

Answer 10

area under curve

Question 11

when to use Suvat

Answer 11

straight line + constant acceleration

Question 12

suvat equations

Answer 12

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

Question 13

stopping distance

Answer 13

thinking + braking. distance travelled between when you first see reason to stop to when vehicle stops.

Question 14

thinking distance

Answer 14

speed * reaction time

Question 15

whats free fall

Answer 15

when object accelerates under gravity with no other force acting on it

Question 16

methods to calculate g

Answer 16

• electromagnet trapdoor: electromagnet holds steel ball above trapdoor. when current switched off ball falls, hits the trapdoor, electrical contact is broken (trapdoor is in a circuit) and timer stops.
• delays in timing
• light gates: 2 light beams, one above the other. when ball falls through first one timer starts and then ends when ball goes through second