Differences between infrasound and ultrasound
Infrasound below 20hz, ultrasound is above 20000hz, humans hear infrasound, cant hear ultrasound
Explain how uv is emitted to visible light in banknotes
This process is called fluorescence, uv emits electrons, electrons change energy levels and chnage orbit, they get in exciyed state leading to UV being emitted as visible light
Explain how sound waves can be used to figure out depth of ocean
Ultrasound pulse release from boat, travels to ocean bed, gets reflected, time there for emission to reciept pulse is measured, speedxtime=distance, half time to measute to calculate depth
One way to reduce percentage of energy transmitted through board
Use thicker board, make board less dense
Explain how momentum and energy both conserved in energy and collision
Equal and opposite forces equal, before collision=after collision, ke=1/2mv^2, some energy dissipared as thermal energy, power= mass x velocity, after collision it equals 0 proving energy and momentum conserved, mometun vector
How to find value of background radiation
Use GM tube, remove any sources nearby that are obvious, measure count in a certain period of time and do count/time to figure out background radiation
What is virtual image
Cannot be projected
How can critical angle for glass be determined
Increase angle of glass, obserbe refracted beam until angle of refraction 90 degrees, angle of incidence critical angle repeat and take average
Why does light not vhange direction as it enter glasd
It reaches a 90 degrees,
Student should use ray and mirror in position how to use
Mark the part the ray light hits, put in normal to the mjrror which perpendicular at point of reflection and use protractor to measure incidence
2 differences between irradiation and radiaoctive contamination
Irradation is outside object and irradation can be prevented by shielding
Explain how scan figure out the location of tumour
Electron and positron annhilatwd, gamma ray emitted, time and distance different
Why should radipactice isotope be near to the person and you
Half life short, shorter time to be used after production
What is ionising
Lose/gain electron
Why do mices hear more than us
Mices more sensitive to higher frequencies whereas humans high frequency to low frequencies, lower intensity for us to hear
Explain how momentum is conserved
Before=after, conservation of momentum, no external force acting, time of collision same, equal and opposute force equal meaning opposite momentum changes, f=ma
Why is it better using nuclear power
Running out of fossil fuels, doesnt affect environment no carbon emission, so no global warming, low running cost, larger power output, risk are terrosist, expensive to set up, nuclear toxic waste lasts long, njclear disaster
What is radiatio. Used for
Irradiation, steellisation
Ehat happens in nucleys of positron emitted
Proton becomes a neutron
How could u determine critical glass in image
Extend graph curve, reach until 90 degrees and check corresponding angles
Explain why temp P reach constant value even though heater remains switched on
P absorbed the thermal energy, p emits thermal energy aswell, rate of absorption=emittion increases with temperature
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Physics21
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Circuits4
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Specimen Papet 1 Higher5
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Conversion Of Units1
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Question Got Wronf5
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Questions Got Wrong 2019 Paper5
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Questions Got Wrong 20184
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Question Wrong 20223
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Questions Wrong 20206
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Specimen Paper Wrong Again6
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Questions Wrong 20191
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2023 Past Paper3
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Radioactivity Questions Wrong3
