Physics Paper 51 Guess

[earthling]

Vacuum may be used to vary pressure too, right?

 

[earthling]

And btw...what's "spirit level"? And what do you mean by reversing hall probe?

 

[usmiunique]

Vacuum may be used to vary pressure too, right?

vacuum pump not just vacuum!

 

[h.alia]

Must the worst acceptable line from Q2 be dotted?? And how to make it pass through all error bars?

it should pass through the top of the topmost error bar and the bottom of the bottommost error bar
and no it has to be 1 straight line with clear labels

 

[h.alia]

Btw, for the rough check the .pdf file teaching A2 practical skills. It's there around pg 66, im not sure, perfect diagram.

Safety

Wear goggles
Water bath cold get hot, spillage
Equipments can be knocked over
Sand box to protect tiles from cracking
USe of tongs to put junction of thermocouple into water bath
If experiment involves sound, use ear defenders.
Light sources could get hot, use gloves
Coil could get hot, use coils, switch off current when not in use
Don't look directly onto light source, use goggles.

Additional details for 4 marks.
Stir water bath to reach uniform temperature
Check for zero error before taking any reading
Use digital voltmeter for accuracy
Switch off current to keep deflection safe/within limits
TO measure depths/lengths in 3-D, use set squares with rule
Use rheostat for constant current
use potential divider for constant voltage.
Repear measurements of lengths/diameter/radius/
thickness at different points and take average
TO measure pressure : Use Manometer/Pressure gauge
To vary pressure : Use pump
Always explain a little theory for extra marks
Explain about calculations using graphs and gradients to earn extra marks
Use vernier calliper, micrometer
Reduce frictional forces using lubricants etc. for mechanical experiments (pulley/inclined planes etc.)
Use spirit level

With hall probe/Magnetism

Hall probe should be perpendicular to magnetic field
Voltmeter across hall probe and dc supply for hall probe (Explain theory about electrons deflection due to magnetic field)
Keep number of turns constant and current constant in coil
Fix hall probe for uniform orientation
Avoid external magnetic fields
Use cross rulers to find the center of the coil
use large current for large magnetic field
repeat experiment with hall probe reversed.

are these for a specific experimiment or in general ?!!