Answer:
(a) = -0.16%
(b) = smaller
Explanation:
given
power = 460 W
potential difference = 120 V
(a) what percentage will its heat output drop if the applied potential difference drops to 110 V ?
we know
.....................(i)
we need to find change in power
..............(ii)
from equations we get



(b)
if we increase temperature resistance will increase and decrease with decrease in temperature and we know power is inversely proportional to resistance so if potential decrease and it would cause drop in power
and due to this increment of heating power resistance will decrease so actual drop in the power would be smaller
Answer:
-22/15
Explanation:
the least common denominator is 15 so first you multiply -2/3 by 5 in both the numerator and denominator making it -10/15
Then you do the same to -4/5 except you multiply the numerator and denominator by 3 giving you -12/15
If you add -10/15+ -12/15 you get -22/15
Explanation :
When an electron jumps from one energy level to another, the energy of atom gets changed.
If a photon gets absorbed, the electron will move to higher energy levels and then fall back to the lower energy levels. Then each time a photon will be absorbed whose energy is given by difference between the initial and final energy levels i.e
In Balmer series, the transition is from higher energy levels to n = 2.
So, the necessary condition for Balmer series is that the electron should be at first excited state or n = 2 level as shown in figure.
<u>Answer:</u>
The modern atomic theory has given by "John Dalton and framed postulates".
<u>Explanation:</u>
The fundamental role of atoms in chemistry is established by the modern theory of atoms mentioned in 1808 for the first time by an English scientist named John Dalton. This consists of three sections such as all matter is composed of atoms, atoms of the same element are the same while atoms of different elements are different, atoms combine to form compounds in full-number ratios.
The unique characteristic of the "number of protons" is that all atoms of the same compound share. While the atoms of the same element i.e having a similar number of protons can have different numbers of neutrons and such elements are called isotopes.