Vasco points a bright red floodlight at a freshly cleaned zinc plate and leaves it there all day. The red light delivers thousands of joules to the plate. By evening, the zinc has not lost a single electron.
The photoelectric effect ejects electrons from a metal. You might expect any light to manage it, given a bright enough lamp or a long enough wait. The first careful observation says no.
Light below that frequency ejects no electrons from that metal.
A more intense lamp below the minimum still ejects nothing.
A longer wait does not help either: light below the minimum can shine on the metal all day and eject nothing.
Red light's frequency is below zinc's minimum, so bright red light on zinc ejects nothing, however long it shines.
Brightness and waiting time do not decide whether electrons come out at all; the light's frequency does.
A dim violet lamp and a bright red floodlight each shine on a clean sodium plate. For sodium, violet light's frequency is above the minimum for ejection, and red light's is below it. Which lamp ejects electrons?
Light below a metal's minimum frequency ejects no electrons, however intense it is.
The bright red light is below sodium's minimum, so it ejects nothing.
The dim violet light is above sodium's minimum, so it can eject electrons.
Only the dim violet lamp ejects electrons from the sodium.
An ultraviolet lamp ejects electrons from a clean zinc plate. Una swaps it for a red floodlight ten times as intense and waits an hour. What does the red light eject?
Red light's frequency is below zinc's minimum frequency for ejection.
Below the minimum, intensity does not matter: the brighter red light still ejects nothing.
Time does not matter below the minimum either, so the hour of shining changes nothing.
The red floodlight ejects no electrons from the zinc.
Bright red light shines on a freshly cleaned zinc plate all day. Red light's frequency is below zinc's minimum for ejecting electrons. How many electrons does the light eject?
A lamp below a metal's minimum frequency for ejection shines on the metal and ejects nothing. Xiomara doubles the lamp's intensity, frequency unchanged. What happens now?
Zelda says: 'Whether a given light can eject any electrons from a given metal depends on the light's frequency.' Is Zelda correct?
For copper, the minimum light frequency for ejecting electrons lies in the ultraviolet. A powerful green laser shines on a clean copper pan for an hour. What does the laser eject from the copper?
A lamp shines on a clean metal plate and ejects no electrons, even at full brightness. Which single change could make the plate start ejecting electrons?
Which statement describes how light below a metal's minimum frequency behaves?