The most probable reason why the magnets won't stick on the refrigerator is that the body of the refrigerator and the magnets have like poles. If both have negative or both have positive poles facing each other, they will repel. In principle, magnets are attracted to opposite poles and like poles repel.

5 0

3 years ago

A quantum well is a region of semiconductor or metal film that confines particles to a small region, resulting in quantized ener

murzikaleks [220]

Answer:

226.2 m/sec

Explanation:

We have given $\Delta x=510nm=510\times 106{-9}m$

The plank's constant $h=6.67\times 10^{-34}$

Mass of electron $m=9.11\times 10^{-31}kg$

Now according to Heisenberg uncertainty principle $\Delta v\geq \frac{h}{2\pi m\Delta x}$

So $\Delta v\geq \frac{6.6\times 10^{-34}}{2\times 3.14\times 9.11\times 10^{-31}\times 510\times 10^{-9}}=226.2m/sec$

5 0

2 years ago

List 5 differences between a compound and an element.

Anuta_ua [19.1K]

Answer:

1.An element consists of the same kind of atoms while a compound is composed of different kinds of atoms.

2.A monoatomic element cannot be split up physically or chemically but a compound can be split up into new substances by chemical means.

3.Only limited number of elements are known in an element whiles number of known compounds are quite large.

4.The property of an element is the property of the atom whiles the property of a compound is quite different from that of it's constituents.

5 . Elements are represented by symbols and numbers.for example Sodium is represented by Na whiles compounds are represented by their chemical formula.for example,Salt is represented by the formula NaCl.

5 0

2 years ago

Energy flow diagram of petrol driven lawnmower​

Energy flow diagram of petrol driven lawnmower