General Science Mixed Quiz: Set 110

A nanometre is 10⁻⁹ m and an ångström is 10⁻¹⁰ m, so one nanometre holds ten ångströms.

The 2011 FSSAI labelling rules made the list of ingredients, nutrition information and the vegetarian or non-vegetarian mark compulsory, but not medical advice on allergies.

Average velocity is total displacement divided by time, and the car ends where it started, so its displacement is zero.

Meiosis makes gametes that differ from one another, and fertilization joins a gamete from each of two parents, so every offspring gets a new mix of genes.

Momentum is mass times velocity, 10 × 10 = 100 N.s, and kinetic energy is half the mass times the square of the speed, ½ × 10 × 10 × 10 = 500 J. Linear momentum, p = mv, measures the quantity of motion and is a vector; its unit…

Above the threshold, the kinetic energy of the ejected electrons rises as the frequency of the light rises, so the statement that it does not change is wrong.

The water at the bottom warms, becomes lighter and rises, while cooler water sinks to take its place, and these convection currents carry heat through the pot.

Crown gall is caused by the bacterium Agrobacterium tumefaciens, which enters through a wound near the base, or crown, of the stem and makes the plant grow rough tumour-like swellings there.

When light enters a denser medium, its wavelength is divided by the refractive index of that medium. The frequency of light is fixed by its source and does not change on refraction.

The pericycle is a layer of cells around the vascular cylinder of the root and stem; it is not part of xylem or phloem.

Pitch is the way our ear senses the frequency of a sound: the higher the frequency, the higher the pitch.

The spring constant is force divided by extension, so its SI unit is newton per metre. Hooke's law says that, within the elastic limit, the restoring force of a spring is proportional to how far it is stretched or compressed: F = −kx.

Electric power equals voltage times current, so the current is 60 W ÷ 240 V = 0.25 A. The relation P = VI comes straight from the definitions: voltage is energy per unit charge and current is charge per second, so their product is energy per second, or power.

This is the incorrect statement, because periodic motion repeats after every interval T, again and again. The time period T of a pendulum is the time for one complete oscillation, that is, the smallest interval after which the bob returns to the same position moving in the same direction.

Among the alkali metals, reactivity with water increases down the group, so lithium, at the top, is the least reactive.

A beam seen from the side is visible only because tiny particles send some of its light sideways. Light travelling in a straight line cannot enter our eyes unless something redirects it towards us.

Two vanadium atoms must balance five oxide ions, each of charge −2, so each vanadium carries +5. In a neutral compound the oxidation states add up to zero.

It contains hydrochloric acid and has a pH of about 1.5 to 2, the lowest of the four, so it has the most hydrogen ions.

Its density is about 0.86 g/cm³, less than that of water, so it floats while it reacts. Potassium is an alkali metal, soft enough to cut with a knife.

Graphite, fullerene, diamond and graphene are all allotropes of carbon, made only of carbon atoms arranged in different ways. Allotropes are different structural forms of the same element.