Systematic is just a certain way of doing something. So science being systematic may just refer to the scientific method or how theories are proved in science by repeating the scientific method over and over again.
Answer:
No, some energy will be dissipated energy due to work of air resistance.
Answer:
Salinometer, also called salinimeter or salimeter, device used to measure the salinity of a solution. It is frequently a hydrometer that is specially calibrated to read out the percentage of salt in a solution.
Explanation:
I hope it is correct answer
Answer:
Mass of receiver is 92 kg
Explanation:
We have given mass of tackler 
Let the mass of receiver is 
When tackler moving alone velocity is
m/sec
And when tackler and receiver is together velocity is
= 2.5 m/sec
So from conservation of momentum





So mass of receiver is 92 kg
Before swinging, T has only potential energy, (no speed)
Ui = mgh
Where h is the vertical displacement of T
From the laws of geometry,
cos45 = (L-h)/L
cos45 = 1-h/L
h/L = 1-cos45
h = L(1-cos45)
Therefore
Ui = mgL(1-cos45)
Proceeding the same way,
Twill raise to aheight of h' due to swing
h' = L(1-cos30)
The PE of T after swing is
Uf = mgh'
Uf = mgL(1-cos30)
Along with the PE , T has some kinetic energy results due to the moment.
Tf = 0.5*mv^2
According to the law of conservation of energy,
Ui = Uf+Tf
mgL(1-cos45) = mgL(1-cos30) + 0.5*mv^2
gL(co30-cos45) = 0.5*v^2
9.8*20*(co30-cos45) = 0.5*V^2
v = 7.89 m/s
<span>The speed f T after swing is 7.89 m/s</span>