Answer: The chemical formula for the compound of these two elements is 
Explanation:
For formation of a neutral ionic compound, the charges on cation and anion must be balanced. The cation is formed by loss of electrons by metals and anions are formed by gain of electrons by non metals.
Here metal lead is having an oxidation state of +4 called as
cation and sulphur non metal has oxidation state of -2 called as
. Thus they combine and their oxidation states are exchanged and written in simplest whole number ratios to give neutral 
The chemical formula for the compound of these two elements is 
That type of bending is called "diffraction" of waves.
Answer:
The tube should be held vertically, perpendicular to the ground.
Explanation:
As the power lines of ground are equal, so its electrical field is perpendicular to the ground and the equipotential surface is cylindrical. Therefore, if we put the position fluorescent tube parallel to the ground so the both ends of the tube lie on the same equipotential surface and the difference is zero when its potential.
And the ends of the tube must be on separate equipotential surfaces to optimize potential. The surface near the power line has a greater potential value and the surface farther from the line has a lower potential value, so the tube must be placed perpendicular to the floor to maximize the potential difference.
Answer:
c. Sound travels slower than light.
Explanation:
We see any thing because of the light emitted or reflected by it. Whereas the sound is carried by the sound waves. The speed of light is more than the speed of sound. This is the reason the family saw the fireworks first and then heard the sound.
The same can be experienced during the sighting of a Jet plane or a rocket where, we see them way before we can hear the roaring sound of its engines.