Daily NEET MCQ- August 20, 2022 - NEET MCQ

In the early 1800s, a German chemist named Dobereiner came up with the idea of classifying elements as per their properties. LAter in 1829, he noticed a similarity in triads (a group of 3 elements). This is how he classified.

According to Dobereiner, in triads, the average weight the 1^st and the 3^rd element are equal to the second one. Li, Na, and K; Ca, Sr and Ba; CL, Br and I satisfy the above conditions. But He, Na and Ar don’t follow the law of Dobereiner Triads.

In the year 1865, an English chemist named John Alexander Newland proposed the law of octaves. It stated that when elements are arranged in their increasing atomic weights, the property of every eight elements is similar to that of the 1^st element.

Mass density (p) = 0.2 kg/m
Length (l) = 20 m
Force = f(x)
= m(x)*g
= 0.2x*g
= 2x
Displacement (d) = 20 m
Work = ∫l0f(x)dx+ (20*g*20)
= ∫2002xdx + 4000
= 4400 J.

Total mass (m) = 50 + 20 = 70 kg
Vertical displacement = 0.2 x 20 = 4m
Horizontal displacement = 0.25 x 20 = 5m
Displacement = (5i + 4j) m
Force = m x acceleration
= 70 x (0i + 10j)
= (700j) N
Work = Force .Displacement
= (0i + 700j) . (5i + 4j)
= 2800 J.

The SI unit of force is Newtons. While Joules, Ampere, and Mole are SI units of energy, current and amount of substance.

Diaphgram is the most important muscular structure in respiratory system of human. At the time of inspiration, diaphgram contracts leading to increase in thoracic volume whereas during expiration it relaxes causing decrease in thoracic volume.

The respiratory rhythm center in the Medulla is primarily responsible for the regulation. Dorsal respiratory group(DRG) generate the basic respiratory rhythm whereas the ventral respiratory(VRG) which remains inactive during normal respiration.

At the time of inspiration diaphgram and external intercoastal muscle contracts leading to increase in thoracic volume. Also, ribs move outward and sternum moves upward.

Dead space air is 150 CC. Dead space air represents the volume of air that does not participate in the gaseous exchange and remains in the lungs. It can’t be expired or inspired or altered.