Questions

True, The luster of a metal is due to presence of free electrons. Luster means shine or soft glow. We know that metals have the quality of reflecting light from its surface.

W is the symbol for chemical element Tungsten or Wolfram.

It is used in making filaments of bulbs.

It takes 248 yrs for Pluto to orbit the Sun.

The main group number for an element can be found from its column on the periodic table. For example, carbon is in group 4 and has 4 valence electrons. Oxygen is in group 6 and has 6 valence electrons.

Mutex is the short form for ‘Mutual Exclusion object’. A mutex allows multiple threads for sharing the same resource. The resource can be file. A mutex with a unique name is created at the time of starting a program. A mutex must be locked from other threads, when any thread that needs the resource. When the data is no longer used / needed, the mutex is set to unlock.

Distance between two Consecutive Crests or two Consecutive Troughs is called Wavelength. But the distance between crest and adjacent trough is half the wavelength.

That is the distance between adjacent crest and trough is called Half the wavelength.