General Science Mixed Quiz: Set 150

The car loses a momentum of 1000 kg × 20 m/s in 0.2 s, so the force is 20,000 ÷ 0.2 = 100,000 N, that is 100 kN.

Nephology is the study of clouds, their formation, classification into types such as cirrus, cumulus and stratus, and their part in rainfall, and it is a branch of meteorology, the science of the atmosphere and the weather.

By Newton's third law, the gravitational force that the first planet exerts on the second is equal and opposite to the force the second exerts on the first.

The wall of a fungal cell is built of chitin, a nitrogen-containing polysaccharide that is also found in the exoskeleton of insects, and it is one of the main reasons fungi were taken out of the plant kingdom and given a kingdom of their own.

A refrigerator moves heat from a cold space to a warmer room, which never happens on its own, and the second law explains what it takes to make it happen.

An adult set of thirty-two permanent teeth has eight incisors for cutting, four canines for tearing, eight premolars and twelve molars for grinding, so there is one canine on each side of each jaw.

For a spherical mirror of small aperture, the radius of curvature is twice the focal length, so f = R/2.

Sertoli cells line the seminiferous tubules and provide nutrition and support to the germ cells as they divide and change into sperms, which is why they are called nurse cells; they are controlled mainly by follicle stimulating hormone.

Sound travels as compressions and rarefactions, while light is a transverse electromagnetic wave. In a longitudinal wave the particles of the medium vibrate back and forth along the direction in which the wave moves.

This committee works under the Ministry of Environment, Forest and Climate Change and appraises proposals for the large scale use and the environmental release of genetically engineered organisms and products, so no transgenic crop may be grown commercially without its clearance.

For resistors in parallel the reciprocals add: 1/11 + 1/22 + 1/33 = 11/66 = 1/6, so the equivalent resistance is 6 Ω. Taking 66 as the common denominator, 1/11 becomes 6/66, 1/22 becomes 3/66 and 1/33 becomes 2/66.

Twelve pairs of cranial nerves arise from the brain and serve the head and neck, among them the optic nerve of sight, the auditory nerve of hearing and the vagus, the longest cranial nerve, which reaches the heart and the abdomen; thirty-one pairs of spinal nerves arise from the spinal…

. Orbits of fixed energy were proposed by Niels Bohr in 1913; Rutherford's experiment said nothing about the energy of electrons.

The receptors that pick up taste are called gustatory receptors, and they sit inside the taste buds on the tongue.

. Oppositely charged ions in an ionic crystal pull on each other strongly from every side, so a great deal of heat is needed to break the lattice apart.

In the Leclanche dry cell the outer container itself is made of zinc and acts as the anode, being oxidised to zinc ions as the cell works, which is why an old cell often leaks when the container is eaten through.

Potassium carbonate comes from a strong base and a weak acid, so statement 1 is wrong, while statements 2 and 3 are right.

Zinc gives up electrons most readily, copper less so and silver least, so the order of electron-releasing tendency is Zn > Cu > Ag.

Every biological molecule, from sugars and fats to proteins and DNA, is built on a skeleton of carbon atoms, which is why carbon is called the basic building block of life.

Lysosomes bud off from the Golgi apparatus as small membrane-bound sacs packed with digestive enzymes. The hydrolytic enzymes of a lysosome are first made on ribosomes attached to the rough endoplasmic reticulum.