Past Mistakes

There is no ________ ___________ from the ________ when the board tips.

reaction force, bank

Description of what happens to forces as someone climbs a ladder:

• Vertical reaction force from ground ________

• Friction force increases

• The _________force from the wall increases

• The weight ___ the ladder increases

increases, reaction, on

Definition of ‘elastic limit’ on a stress-strain curve

• If a material is stretched up to its elastic limit and released, it will ____ to its original shape.

return

A pair of equal and opposite turning forces is called a __________.

couple

To reduce uncertainty in the measurement of a wire clipped to a ruler, a student could ______the wire to the ruler to reduce _________error.

reduce, parallax

150N, _______

clockwise

C

The duration of flashes on a strobe should be as short as possible ________difference between the top and bottom of the object.

blurry, difference

After passing through a diffraction grating, light rays with a path difference of one wavelength will ________ to form the first maxima.

superpose

When taking readings to determine a value using a diffraction grating, it is better to use a lower order n maxima, as higher order maxima are less ________, and may not be fully in ____.

defined, view

If a freely vibrating string is lightly touched at its midpoint what is the effect on the frequency of the sounds heard?

A: There is a forced ______, so only frequencies with a node are heard, e.g. the __________ and fourth harmonic frequencies.

note, second

A = down anti-______ or _____ anti-down

B = electron

C = anti-electron neutrino

strange, strange

______ nuclear

strong

• The strangeness of X is -1

• The strangeness of the ____ and neutron are both zero.

• So strangeness changes from -1 to 0

• This can only occur in the _____ interaction.

pion, weak

Stable particles:

• Proton

• Electron

• ______ neutrino

• Photon

• And all their antiparticles

electron

• The process involves the ______ of electrons which are negatively charged.

• Any electrons ejected will only make the positive charge greater.

ejection

• To demonstrate threshold frequency, the _____ should be kept the same, and the light source varied.

• To demonstrate work function, the ____ ______ should be kept the same, and the metal varied.

metal, light source

• The equation E=hf-phi gives the maximum kinetic energy released because the work function is the _______ amount of energy needed to ________ the electron from the metal’s ________.

• Also, the maximum kinetic energy corresponds to the emission of surface electrons, whilst electrons from _______ in the metal’s will be emitted with _______ kinetic energy.

minimum, release, surface, deeper, smaller

When discussing how total resistance/ potential difference changes, mention that the ___ of the voltage across each component equals the cell voltage.

sum