General Science Mixed Quiz: Set 188

The power turned into heat in a wire carrying a current I is P = I²R, and the resistance of a wire is R = ρl/A, where ρ is the resistivity of its material.

Khesari dal, botanically Lathyrus sativus and also called grass pea, is a hardy pulse that survives drought and is therefore sometimes mixed with arhar dal or besan.

A primary rainbow comes from light that is refracted into a raindrop, reflected once inside it and refracted out again, and it is the brighter, inner bow.

The correct answer is A, Kerria lacca, earlier named Laccifer lacca, a tiny scale insect whose female settles on the twigs of a host tree, sucks its sap and secretes the resin we call lac.

LIGO uses laser beams in long perpendicular arms to detect the tiny stretching of space caused by gravitational waves. LIGO has two detectors in the United States, at Hanford in Washington and Livingston in Louisiana, each with arms 4 km long.

For a swinging pendulum, the component of the bob's weight along its path always pulls it back towards the lowest point, so gravity acts as a restoring force.

The friction between the blocks is the only force that drags the top block along, and its largest possible value is μ times the normal force from the top block.

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.

The average atomic mass is the weighted mean of the isotope masses, taking each in proportion to how common it is.

Egg white is mostly water and protein, and heat denatures these proteins so that they set into an opaque white solid.

In yeast the pyruvic acid formed by glycolysis is decarboxylated and then reduced to ethyl alcohol, a process called alcoholic fermentation, which is the basis of brewing and of the rising of dough.

It states that a body immersed wholly or partly in a fluid experiences an upward buoyant force equal to the weight of the fluid displaced, so the apparent loss in weight of the body equals the weight of the displaced fluid.

Once a ductile specimen passes its ultimate tensile strength, the deformation stops being uniform and concentrates in one short length, which draws out into a narrow waist.

Veins usually carry blood low in oxygen back to the heart, but the pulmonary veins are the exception. After blood picks up oxygen in the lungs, four pulmonary veins, two from each lung, bring this oxygen-rich blood to the left atrium of the heart.

Nitrogen, phosphorus and potassium are the three primary nutrients, and a fertiliser that carries two or more of them in one chemical compound is called a complex or mixed fertiliser; diammonium phosphate, which supplies both nitrogen and phosphate, and the NPK grades sold by number are the familiar examples.

It is formed from the roots of the lower spine, passes through the buttock and runs down the back of the thigh to the leg and foot, and its compression by a slipped disc causes the pain called sciatica.

When three forces are represented by the sides of a triangle taken in order, their vector sum is zero, because the three sides close the triangle, so the body cannot be pushed away; but the lines of action are different, so the system reduces to a couple.

The field inside a long solenoid is directly proportional to the number of turns per unit length, so doubling n doubles the field.

A compound microscope magnifies more when both its lenses have short focal lengths. In a compound microscope the objective forms a real, enlarged image, and the eyepiece magnifies it further like a simple magnifier.

The mass of one mole of any substance, expressed in grams, is by definition its molar mass. One mole contains the Avogadro number of particles, about 6.022 × 10 23, so the molar mass links the mass we can weigh to the number of atoms or molecules present.