General Science Mixed Quiz: Set 196

Torque is r into F into the sine of the angle between them, and since the force here is perpendicular to the rod the sine is one, so the torque is simply 0.5 multiplied by 20, that is 10 newton metre.

Dynamic viscosity measures how strongly a fluid resists flowing, and in the centimetre gram second system it is measured in poise, a unit named after the French physician Jean Louis Marie Poiseuille, who studied the flow of blood in narrow tubes.

The time period of a simple pendulum is two pi times the square root of the length divided by g, in which the mass of the bob does not appear at all; a heavy bob and a light bob of the same length keep the same time, which is the…

A mercury barometer balances the pressure of the atmosphere against a column of mercury, which stands about 76 centimetres high at sea level.

Inserting a plate of thickness t in one arm makes the light cross it twice, so the extra path introduced is twice the thickness times the quantity refractive index minus one.

Haemodialysis uses a machine called an artificial kidney to clean the blood of a patient whose kidneys have failed.

A second's pendulum is one whose time period is exactly two seconds, so that each swing from one side to the other takes one second.

Rust of wheat is indeed a fungal disease, caused by species of Puccinia, and it is named from the reddish brown spores that appear in streaks on the leaves and stem.

Only a transverse wave, in which the vibrations are at right angles to the direction of travel, can have those vibrations restricted to a single plane by a Polaroid.

A human body cell has 46 chromosomes arranged in 23 pairs, of which 22 pairs are autosomes, the chromosomes that are alike in both sexes, and the remaining pair is of sex chromosomes, XX in a female and XY in a male.

The time period varies as the square root of the length, so multiplying the length by four multiplies the period by the square root of four, that is by two; to double the period of a pendulum its length must be made four times.

An ammeter measures the electric current flowing in a circuit, in amperes. An ammeter is always connected in series with the part of the circuit whose current is to be measured, so that the whole current passes through it.

The light reflected from the upper surface of the thin film and the light reflected from the lower surface travel slightly different distances and interfere.

Deposition is the direct change of a substance from the gaseous state to the solid state, without passing through the liquid state in between.

The time period varies inversely as the square root of g, so if g falls to one sixth, the period is multiplied by the square root of six, about 2.45 times; the pendulum swings more slowly and a pendulum clock taken to the moon would lose time badly.

The correct answer is B, pascal second, equal to a newton second per square metre, which follows from Newton's law of viscosity, where the shearing stress in pascals is divided by the velocity gradient in reciprocal seconds.

The fringe width equals the wavelength multiplied by the distance of the screen and divided by the separation of the two slits.

Potential energy is proportional to the square of the displacement, so it is greatest where the displacement is greatest, that is at the two ends of the path, where the body is momentarily at rest and its kinetic energy is zero.

By Malus's law the intensity transmitted by the second Polaroid is the intensity falling on it multiplied by the square of the cosine of the angle between the two transmission planes.

In simple harmonic motion the acceleration equals minus omega squared times the displacement, so it grows with displacement and is greatest at the ends of the path, where its value is A omega squared and it points back towards the centre.