Practise Edexcel IAL Physics 1.1.1 by applying suvat equations to acceleration, free-fall, braking and s–t² graph relationships.
When water vapour in the atmosphere cools it condenses, forming tiny drops of water. These drops increase in size by colliding with each other and fall back to the ground as rain.
Some plants have adapted to high rainfall by having a specialised shape and waxy leaves. This allows rain to slide down a leaf and off the end as a series of drops.
Water falls from a leaf at a steady rate of five drops per second.
As each drop reaches the ground, there are four drops above it in the air.
Calculate the height of the leaf from the ground. It can be assumed that the drop at the highest position has just left the leaf.
Height of leaf =
Use of s=ut+1/2at2 with u=0
(accept use of t =0.2 s,0.25 s,0.75 s,1.0 s )
- See 0.8 s for the time since the drop left the leaf
- s=3.1 m
(1)
(1)
(1)
Example of calculation
s=1/2×9.81 N kg−1×(0.8 s)2=3.14 m
3