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LAWS/DEFINITION

1. INTRODUCTION TO PHYSICS

Sensitivity Ability of instrument to detectsmall change of quantitymeasured.

Accuracy Abili ty o f instrument t o givereading closer to actual value.

Co nsistency Ability of instrument to giveconstant reading every timethe measurement is made

Parallax error hen eyes is notperpendicular to the scalewhen take the reading

Zero error hen the instrument givereading when it is suppose tobe zero

2. FORCES AND MOTION

eight (N) Gravitational force (N)

Gravitational

acceleration, g (10ms

-2)

Accelerati on due to

gravitational force.

Elasticity Property of matter that enablesan object to turn to its originalsize and shape when the forcesacting on it are removed.

Inertia Tendency of object to remainat rest or moving withconstant velocity

Impulsive force Rate of change of momentum

Impulse Change of momentum

3. FORCES AND PRESSURE

Pressure Force acting normally to theunit of surface area.

ArchimedesPrinciples

A body th at is who lly orpartially immerse in liquid, thebuoyant force = weight ofliquid displaced

Bernoulli principle Pressure of the fluid is lowerwhen speed of the fluid ishigher

4. HEAT

Thermalequilibrium

hen net rate heat transferbetween two bodies is zero

Heat Type of energy

Temperature Degr ee of hotness

Specific heatcapacity

Energy required to incr ease theemperature of 1 kg substance

by 1

o

C.Heat capac it y Energy requi red to changeemperature of object by 1

oC

Thermalequilibrium

Net heat transfer between twobodies is zero.//temperature ofwo body touching each other

is equal.

5. LIGHT

Cr it ical angle Angle o f incidence when angleof refraction=90

o

Focal po in t Po in t t hat all par all el li gh t wit hprincipal axis are converge to.

Focal length oflens

Distance between focal pointand the optical center

Focal length ofconcave mirror

Distance between pole and theprincipal focal point

Snell law. Sin i------- = const antSin r

Ref rac ti ve i ndex Sin i-------Sin r

Refraction of light. Light change its speed anddirection when travel throughdifferent medium

6. WAVES

Monochromaticlight

Light that has one wavelengthonly

Constructiveinterference

hen trough meettrough//when crest meet crest

Destructive

interference

hen rough meet crest

Frequency Number of oscillation in 1s

avelength Distance between 2consecutive trough/crest/wavefront

Diffraction ave phenomenon when waveravel through obstacle of

gap/slitCoherent sources Two sources that have same

frequency and same phase.

7. ELECTRICITY

Ohms Law Curren t i s d irec tly pr opor ti onalo the voltage when physical

condition and temperature isconstant,

9V battery The battery supply 9J ofelectrical energy to tr ansfer 1Cof charge

9W, 12V bulb The bulb use 9J of elec tr icalenergy in 1s when connected to12V power supply

8A 8C of charges has been transferin 1s

Emf The work done by a source indriving a unit of charge arounda complete circuit.

Potentialdifference//voltage

ork done to transfer 1C ofcharge from one point toanother

Power Amount of energy use in 1C

8. ELECTROMAGNETISM

Electromagneticinduction

Production of induced currentin solenoid when the solenoidcut the magnetic field

Catapul t fi el d Non-uni fo rm magnet ic f iel d.

Electromagnet Soft i ron winding wi th solenoid,has magnetic field whencurrent flow through themagnet and lost it when nocurrent flow.

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Lenz Law Induced current produced inhe solenoid always oppose the

effect causing it

Determine thedirection of forceproduced bycurrent carryingconductor inmagnetic field

Use Fleming Left Hand Rule

Determine pol e ofsolenoid

Use right hand grip rule.

Determine thedirection ofcurrent producedby generator

Use Flemings Right Hand Rule.

9. ELECTRONICS

Thermionicemission

Electron release by a hot metalsurface

Logi c gates El ec tr on ic swi tch t hat have oneor more inputs but have onlyone output

10. RADIOACTIVITY

Radio isotope The i so tope w ith uns tab lenuclei that emit radioactiveradiations.

Nuclear fission A process of breaking up heavynucleus into lighter nucleus

Nuclear fusion A process of merging lighternuclei into heavy nucleus.

Half life Time taken for un-decay nucleibecome half from its originalamount.

Bet a par ti cle Fas t m ov ing el ec tr on .

Alpha par tic le Helium nucleus

Gamma ray An electromagnetic wave

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Precautionary steps during experiment

Eye must be perpendicular to the scale ofammeter/voltmeter/meter ru le when take thereading.

All connection must be t igh t enough.

Take several reading and find t he average.

For each value of manipulated variable, takeseveral reading of r esponding variable and findthe average

Do not on the switch for longer time.

Turn off the switch when not take the reading.