Answer:

Explanation:
Using the conservation of energy we have:

Let's solve it for v:

So the speed at the lowest point is 
Now, using the conservation of momentum we have:

Therefore the speed of the block after the collision is 
I hope it helps you!
Answer: A crest is the highest point the medium rises to and a trough is the lowest point the medium sinks to. It is also a point on the wave where the displacement of the medium is at a maximum.
Answer:
D. crystalline solid that conducts current under certain conditions
Explanation:
Semiconductors are crystalline solids that has the ability to conduct electrical currents but on certain conditions e.g heat. The conduction of semiconductors is less than that of conductors (metals) but more than insulators (nonmetals), hence, they are said to be intermediates of conductors and insulators in terms of electrical conductivity.
Examples of semiconductors are silicon, boron, carbon, germanium, arsenic etc.
Answer:
Explanation:
If E₀ is the electric field outside the smaller sphere and r is the radius of larger sphere.
E₀ = kQ/r²
The radius of the larger sphere is 3r and the charge on both sphere is same then the electric field outside the larger sphere is given as
E = kQ/(3r)² = kQ/9r² = 1/9 (kQ/r²)= 1/9 x E₀
hence the correct option is e.