As they are Alkali metals (group 1), they are extremely reactive in both air and water so must be stored in kerosine to stop them from reacting with the air or water.
Answer:
153.6 kN
Explanation:
The elastic constant k of the block is
k = E * A/l
k = 95*10^9 * 0.048*0.04/0.25 = 729.6 MN/m
0.12% of the original length is:
0.0012 * 0.25 m = 0.0003 m
Hooke's law:
F = x * k
Where x is the change in length
F = 0.0003 * 729.6*10^6 = 218.88 kN (maximum force admissible by deformation)
The compressive load will generate a stress of
σ = F / A
F = σ * A
F = 80*10^6 * 0.048 * 0.04 = 153.6 kN
The smallest admisible load is 153.6 kN
Answer:
the transmission axis of polarizing sheet makes an angle of
with the horizontal
Explanation:
We have given that intensity of light incident on the sheet 
Average intensity of light emerging from a polarizing sheet 
We have to find the angle between transmission axis with the horizontal
Intensity of light polarizing from sheet is equal to 
So 



So the transmission axis of polarizing sheet makes an angle of
with the horizontal
06758 m
Explanation:
it is correct because that is what
When two sound waves of similar frequency interfere with each other, there is a fluctuating sound heard which is periodic and repeating. This fluctuating sound is called beat. Beat frequency( number of beats per second) is equal to the difference of the frequency of the two sound waves.
So, sound waves of frequency 400 Hz and 404 Hz will produce 4 beats per second.