As Exam Questions Flashcards
state and explain what feature of the graph shows that the car’s deceleration was uniform
the gradient respects the deceleration, the gradient is constant
state the difference between a scalar and vector quantity
vector quantise have direction and quality
two examples of vector quantity
displacement
velocity
state Hooke’s law
the amount of force is directly proportional to the extension up to the limit of proportional
explain what a stationary wave formed on the string
progressive waves travels from the centre to end
two progressive waves travel in opposite direction along the string
waves have same frequency (same amplitude)
explain why this light is totally internally reflected at the water surface
(critical angle)
angle of incidence exceeds critical angle
light passing through each slit spreads out. what is this effect?
diffraction
Explain the formation of the fringes seen on the screen
- inference
- where the light overlaps
- bright fringes are formed where the slits overlap
- dark fringes are formed when light cancel;s
- the light is coherent
- reinforcement occurs where light waves are in phase
- cancellation occurs when the waves are 180 out of phase
describe how the appearance of the fringes would differ if white light had been used instead of red light
-central fringe would be white
-side fringes of spetra
-dark fringes would be closer together
-bright fringe would be blue on the side nearest the centre
white fringes merge away from. the centre
-bright fringes wider
what is meant meant by an isotope
same number of proton but a different number of neutrons
explain what is meant by ground state of an atom and describe the process that is taking place in the atoms emitting photons.
Ground state is the lowest energy state. Photons are emitted when the atom is excited by gaining energy and when the atom dexcitates photons of different frequencies are emitted.
the electron moves down an energy level realising an proton
electron in atoms can only occupy certain energy levels
electrons collide with orbital electron
every particle will eventually decay to …
proton
state and explain the effect on the emitted electrons of increasing the frequency of the light
electron realised would have more kinetic energy and increasing the frequency of the protons increases
state and explain the effect on the emitted electrons of increasing the intensity of the light
more protons stake the metal surface so more electrons would be emitted
describe the procedure the student would follow in order to obtain an I-V curve for the semiconductor diode (6)
you would measure the current by using an ameter and the voltage through a voltmeter, you would plot the points on a graph with current on the x-axis and voltage on the y-axis. you would repeat the readings.
- make the circuit
- reverse the power supply to get negative readings
- vary the voltage
state and explain the effect on the oscilloscope trace if the time base is switched off
vertical line is formed
of length equal to twice peak voltage because the trace no longer moves horizontally
Write down one factor tyat could affect the drivers reaction time
Alchol
A fielder, as he catches the cricket ball he pulls his hand backwards
Explain why this action reduces the force on his hands
A cricketer lowers his hands while taking a catch to decrease the change of momentum, they increase the time by pulling in backwards
How does the resistance of a filament lamp change as the temperture of the filament change?
The resistance of the lamp increases as the temperature of filament increases so when the filament is hot then the resistance is high
Explain the difference between a transverse waves and longitudinal wave
Longtiudual waves
The vibrations are along the same direction as the direction of travel
Transverse waves
Osculate at right angel to the direction of movement
When the door is open, the person can hear the sound (from the TV) but cant see the television
Sound waves can diffract through the gap because the wavelength deceases
What happens during the process of nuclear fission
A nucleus hits the uranium nucleus which then splits realesing another neutron
Inside which part of the nuclear power station would molybdenum be produced
Nuclear reactor
What is meant by the term half-life
The amount of time needed for the number of nuclear atoms to half