physics spa tmr.
omgomgomg.
i think my god's so busy lately cos i've been like calling him all day tday.
:D
shall dedicate the below to all physics students.

Key Sources of Error (for the jockey experiment)

1) The wire becomes too hot after some time and thus its resistance changes, which may result in inaccurate measurement of current or potential difference values.

2) There are kinks in the wire which cannot be straightened out. this affects the accuracy of the length measured and in some cases, may cause slight variations in the resistance of the wire since resistance is dependent on the length.

3) The wire is not of uniform thickness thus the resistance readings taken at each point may vary as resistance is dependent on cross-sectional area of the wire.

Main things to note:

1) Use crocodile clips to clip the hook of the battery cell.
-if the wire with the 'u-shaped' metal part is used, the loose circuit will be penalised.
-if u're unlucky and get those teachers who go around pulling your circuits, take note of this point.
2) For rheostat, clip DIAGONALLY!
-if clipped at the bottom two metal knobs, the current flow will experience maximum resistance as the current flows through all the metal coils, resistance will not vary even if the movable part is shifted.
-if clipped at the upper two knobs, the current flow will experience minimum resistance as the current flows through the metal rod of minimal resistance, similarly, resistance will not vary even if movable part is shifted.

3) For measurements, follow the precision of the instruments. For calculated values, follow the sig. fig. of the previous column.
-for this, pls refer to spa skills handout for clearer understanding :]

4) DRAW GRAPH BIG BIG! :D
-use a good scale and ensure that graph spans across more than two-thirds of the graph paper.
-if graph is a straight line[even if not passing through origin], relationship is linear.

P.S. MY BROTHER'S BACK FROM KOREA WITH LOTS OF KIMCHI!air-flown!-.-