Answer:
Ratio of length will be 
Explanation:
We have given time period of the pendulum when length is
is 
And when length is
time period 
We know that time period is given by

So
----eqn 1
And
-------eqn 2
Dividing eqn 2 by eqn 1

Squaring both side

Answer:
Apparent depth (Da) = 60.15 cm (Approx)
Explanation:
Given:
Distance from fish (D) = 80 cm
Find:
Apparent depth (Da)
Computation:
We know that,
Refractive index of water (n2) = 1.33
So,
Apparent depth (Da) = D(n1/n2)
Apparent depth (Da) = 80 (1/1.33)
Apparent depth (Da) = 60.15 cm (Approx)
Look on this website http://hyperphysics.phy-astr.gsu.edu/hbase/phyopt/sinslit.html
It takes more energy to remove the second electron from a lithium atom than it does to remove the fourth electron from a carbon atom because its inner core e, not valence e. C's 4th removed e is still a valence e. And also <span>because more nuclear charge acting on the second electron, it is more close to the nucleus, thus the the protons attract it more than the 4th electron.</span>
Is halved. A 6Ω resistor connected to a voltage source which voltage is decreased from 12V to 6V the current passing through the resistor is halved.
The key to solve this problem is applying Ohm's Law V = R I, clearing I from the equation, we obtain I = V/R. Then, the current is directly proportional to the voltage and inversely proportional to the resistance.
V = 12V and R = 6Ω
I = 12V/6Ω = 2A
V = 6V and R = 6Ω
V = 6V/6Ω = 1A
As we can see the current is halved if the voltage descreased from 12V to 6V