A siren emitting sound of frequency 500 Hz is going away from a static listener with a speed of 50 m/sec The frequency of sound to be heard, directly from the siren

The Doppler’s effect is applicable for

Two vibrating tuning forks produce progressive waves given by y_l = 4 sin 500 pt and Y₂ = 2 sin 506pt Number of beats produced per minute is

If A = {1, 2, 3}, B = {3, 4}, C = {4, 5, 6}, then is equal to

x may have values:

In a group of children, 35 play football out of which 20 play footballs only, 22 play hockey; 25 play cricket out of which 11 play cricket only. Out of these 7 play cricket and football but bot hockey, 3 play football and hockey but not cricket and 12 play football and cricket both.
How many plays hockey only ?

In the evaporation of water, the entropy:

The enthalpy changes at 298 K in successive breaking of O-H bonds of water are
and The bond enthalpy of O-H bond is:

Energy required to dissociate 4 g of gaseous hydrogen into free gaseous atoms is 208 kcal at '250 C The bond energy of H-H bond will be:

A vector of magnitude 10 and perpendicular to and is

The vectors and have their initial points at (1, 1). The value of so that the vectors terminate on one straight line is

The adjacent sides of a parallelogram are and where and are the usual unit vectors along the positive directions of x and y-axes respectively. Then the angle between the diagonals is

If vector and are the sides of a triangle ABC, then the length of the median AM, is

____________ pairs of parallel lines are there in regular hexagon?

Hexagon is a closed figure which has six sides and six corners. Given is a regular hexagon, which means it has equal interior angles and equal side lengths. So, there will be 3 pairs of parallel lines in a regular hexagon.
>>>Hence, we can say that the Hexagon has 3 parallel pairs.

Statement–I : In gravity free space, the liquid in a capillary tube will rise to infinite height
Statement–II : In the absence of gravity , there will be no force to prevent the rise of liquid due to surface tension

Statement–I : The velocity of horizontal flow of a ideal liquid is smaller where pressure is large and vice versa. Statement–II : According to Barnoullis theorem for the stream line flow of an ideal liquid, the total energy per unit mass remains constant