Practice MCQ Questions and answers on Physics-GK

The gravitational constant is dimensionally represented as M^-1 L³ T^-2.

Angular momentum has the same dimensions as that of Planck's constant.

The period of oscillation of 3 cm microwaves is 1 × 10^-10 (Physics, Volume 1, by Halliday). The period of oscillation is the smallest interval of time in which a system undergoing oscillation returns to the state it was in at the beginning of the oscillation.

In Simple Harmonic Motion, the frequency of the oscillation (f) is the number of oscillations per second which is expressed as
f = 1 / T
where T is the time period (the time for the oscillator to complete one cycle). Now, when a person sitting on a swing stands up on the swing, the effective length of the swing decreases. When length decreases, the time period also decreases. Since frequency of oscillation is inversely proportion to time period, it increases in the present case of man standing up on the swing.

Basic conditions to execute simple harmonic motion are: (i) There must be an elastic restoring force acting on the system, (ii) the system must have inertia, and (iii) the acceleration of the system should be directly proportional to its displacement and is always directed to mean position.

When a body moves about a mean position in such a way that the acceleration is proportional to the displacement and is always directed towards the mean position, the body is said to execute a simple harmonic motion. The motion of a simple pendulum falls under this category.

Boyle's law is a relationship between pressure and volume.

Silver has the maximum thermal conductivity.

P1V1 = P2V2 relates to the ideal gas law.

The metal ball can be considered to be made up of several layers of thinner ones. On heating each of these layers will increase in radius. As the inner most layer also increases its radius, the volume inside it i.e, the volume of the hollow portion will also increase.