Question

see attachment

Answer 1

@Callisto @whpalmer4

Answer 2

K=1/2mv^2...... mass stays the same through out the slide... so we only need to look at the speed of the objects:

velocity increases down the slide due to gravity, so the kinetic energy must increase as the object slides down, hence we can eliminate graph (1) and (2) because kinetic energy is decreasing in that case

for slide A, as you can tell... the gradient is more vertical at the start and becomes more horizontal to the end... i.e. the absolute value of the gradient is decreasing down the slope.... so the speed is increasing at a faster rate at the start of the slide due to gravity and hence acceleration is greater and kinetic energy is increasing rapidly.... as the object slides to the bottom, the acceleration decreases due to the slide being more horizontal and hence the speed isnt increasing as much.... the kinetic energy is not increasing much either since it depends on speed...... putting it all together: the kinetic energy graph of slide A should be as such: it should increase rapidly at start and stabilize when it gets to L because of no increase in speed.... this is represented in graph (4)

use the same logic and you'll see that it applies to other kinetic energy plots on graph (4)

Answer 3

Excellent discussion by @tushara!