Nikhilesh has a small piece of metal and a thread. He wants to find whether the metal is a magnet or not. Which of these things would he need?

Asample of silver (with work function ? = 4.52 ev) is exposed to an ultraviolet light source (? = 200 nm), which results in the ejection of photoelectrons. what changes will be observed if: silver is replaced with copper (? = 5.10 ev) more photoelectrons ejected no photoelectrons are emitted fewer photoelectrons ejected more energetic photoelectrons (on average) less energetic photoelectrons (on average)

Surface currents are caused by blank space . question 14 options: surface currents are caused by? differences in water temperature high salinity differences in density wind forces

Compare and contrast refraction of light and sound will give brainliest