8.5 - Motion graphs Flashcards
1
Q
define displacement
A
distance in a given direction
2
Q
displacement-time graph
- of a ball is thrown upwards and caught after falling back down
- describe and explain the shape of the graph
A
- initial large positive m = high velocity from the thrower
- ball sizes, velocity decreases = m decreases (due to deceleration of g)
- max height is reached when m=o, thus v=0
- as the ball descends, v becomes increasingly negative, thus m becomes increasingly negative (due to acceleration due to g)
3
Q
distance-time graph
- of a ball is thrown upwards and caught after falling back down
- compare the graph to the displacement-time one
A
- same graph shape as s-t for the first half, until the ball reaches its max vertical height
- afterwards, the distance continues to increase to a slowly curving up the curve. since m = speed and the distance cannot be -ve
4
Q
define velocity
A
speed in a given direction
5
Q
for a v-t graph
1- what does m =
2- what does the area under the graph =
A
1- acceleration
2-displacement
6
Q
v-t graph of a ball thrown up and caught
- what does the point where the graph intercepts the t-axies represent
A
the maximum hight, (v=0)
s = u/g
7
Q
v-t graph of a bouncing ball, intaly dropped
(down = +, up = -)
- what happens to the peak velocities and the area under the graph the more bounces the ball does
A
- peak velocities and the area under the graph (displacement) decreases
8
Q
What type of data logger can be used during motion practices to produce a s-t / v-t graph
- how does it work
A
ultrasound position detector
- automatically records the distance of an object from the sensor several times a second. attache to a computer with graph drawing software tp produce the graphs
9
Q
what are the 3 main advantages of dataloggers over traditional method
A
- more accurate data (removes human reaction times)
- higher sample rate
- data displayed in real time
