Daily NEET MCQ- April 26, 2022 - NEET MCQ

Torque = NIBA sinθ.
Torque = 50 × 20 × 0.2 × 200 × 10^-4 × sin (90)
Torque = 4Nm.

Torque (Max) = NIBA.
Τ_max = 400 × 10³ × 0.2 × 320 × 10^-4
T_max = 2560 Nm.

The band theory assumes that atomic orbitals of the atoms of the crystal combine to form molecular orbitals which are spread over the whole crystal structure. Hence, the number of atoms is directly proportional to the number of molecular orbitals formed.

A metallic crystal has valence electrons in the valence band and free moving, delocalized electrons in the conduction band. For a metal, these two bands are very close to each other.

Semiconductors have completely filled valence bands and completely empty conduction bands. The energy gap between the two bands is relatively small and can be overcome by supplying heat, which excites some electrons to the conduction band, thus allowing the conduction of electricity.

Honey bee is a social, colonial and polymorphic insect with three main castes-fertile female or queen, males or drones and sterile female workers. Queen receives all the sperms required for its life during nuptial flight with drones.

Queen secretes an antiqueen substance, a pheromone, from its glands. It inhibits worker bees to build another royal brood chamber and produce royal jelly for others. The queen lays 2000 fertilised eggs per day. Eggs hatch to give rise to new worker bees which are sexually sterile females.

Worker bees are differentiated into sanitary bees (early few days), nurse bees (first month, feeding larvae and queen), farmer bees, guard bees, builder bees (producing bee wax, building and repair of the hive) and foragers (collecting honey).

Some forager bees function as scout bees that search for new feeding places. Scout bees communicate the position of a food source by round dance if it is less than 75 m and tail wagging dance for longer distances.

Apiculture is highly useful. It provides us with honey which is a near-neutral aromatic tonic, laxative and sweetening syrup. Beeswax is used in cosmetic creams, ointments, paints, polishes and smokeless decorative candles. Bee venom is used in the treatment of Rheumatoid arthritis.