Right a couple of questions from w08 (Link: http://www.freeexampapers.us/IGCSE/Physics/CIE/2008%20Nov/0625_w08_qp_03.pdf)
1) d) ii) - how to work out average speed?
2) d) - why include 200g mass as well?
5) c) - why 16.3-2.1, I don't get it.
d) i) - why series and not parallel?
9) a)
Sorry for the flooding of qu.
Ivo you can't always find the distance using the average. If it isn't available, use a different formula. Here, my teacher taught me a very good one which can be used. Its distance=(initial speed)xtime+ 0.5(mass)(final velocity)^2 (squaring on final velocity). Pluck in the values and you'll get the right answer.
In case of forces, if in equilibrium, sum of forces in one direction is equal to sum of forces in other direction. Here downward forces (due to weights) AND the disc have to be used (the disc will also be pulled by gravity). The poor pivot will have to balance all of em'
For 5 c, I've got no idea. Shazzizle gave an odd explanation on Page 137.
For 8, it's series. In parallel they'll light with full brightness (since each gets the mains voltage, current blah blah). In series it's normal brightness.
For 9, the easiest idea is to pump water higher. It's almost in every text book. No capacitors since they can't be charged with AC (Thanks VIN!!!!!!)