Answer: A.The total number of energy levels the electron can jump to.
Explanation:
Spectral lines are bright or dark lines over continuous spectrum which occur due to emission or absorption of energy.
When an electron jumps to or from one energy level to another energy level, spectral lines are produced. The range of spectral lines depends on the number of energy levels available to which the electron can jump. This depends the amount of energy gained/lost by the electron.
Thus, the correct answer is: A.The total number of energy levels the electron can jump to.
The mechanical energy of an object is the sum of its potential and kinetic energy.
Because the ball is on the ground, its potential energy is 0.
Its kinetic energy is given by:
K.E = 1/2 mv²
K.E = 1/2 x 1 x 2²
K.E = 2 J
Mechanical energy = 2 + 0
Mechanical energy = 2 J
The answer is B.
Answer: Earth's magnetic field has flipped its polarity many times over the ... Earth has settled in the last 20 million years into a pattern of a pole reversal about ... And while reversals have happened more frequently in "recent" years, when ... per year, as opposed to about 10 miles per year in the early 20th century.
Explanation:
Answer:
D. Hydrogen combines with oxygen to form water.
Explanation:
Hydrogen combining with oxygen to form water is a typical example of chemical reaction.
During a chemical reaction, atoms of elements are rearranged. Most chemical reactions obey the law of conservation of mass which states that "matter is neither created nor destroyed in a chemical reaction but atoms are simply rearranged".
The other choices given are nuclear reactions. In such reactions, atoms are not rearranged but are simply destroyed and made in the process.
