JEE Main Class XI Weekly Mock 19 for JEE & BITSAT Exams

Question 1

The number of common chords to the parabolas x = y² - 6y + 11 and y = x² - 6x + 11 is

Question 2

The tangent to the parabola 4x = y²+2y-7 which is normal to the circle (x-2)² + (y-3)² = 1 is of slope

Question 3

The vertex of the parabola y² = 8x is at the centre of a circle and the parabola cuts the circle at the ends of its latus rectum. Then the equation of the circle is

Question 4

The co-ordinates of the point on the parabola y² = 8x, which is at minimum distance from the circle x² + (y + 6)² = 1 are

Question 5

The equation of common tangent to the parabolas y² = 4ax and x² = 4by is

Question 6

A source of frequency n and an observer are moving on a straight line with velocities a and b respectively if the source is ahead of the observer and if the medium is also moving in the direction of their motion with velocity c (the velocity of sound being v) then the apparent frequency of sound heard by the observer would be

Question 7

A whistle sends out 256 waves in a second. If the whistle approaches the observer with velocity 1/3 of the velocity of sound in air, the number of waves per second the observer will receive-

Question 8

A racing car moving towards a cliff sounds its horn. The driver observed that the sound reflected from the cliff has a pitch one octave higher than the actual sound of the horn. If V = the velocity of sound, the velocity of the car is-

Question 9

For a certain organ pipe, three successive resonance frequencies are observed at 425 Hz, 595 Hz and 765 Hz respectively. If the speed of sound in air is 340 m/s, then the length of the pipe is -

Question 10

A metallic rod of length 0.88 m is arranged in Kundt’s tube by clamping at its midpoint. If the distance between two consecutive nodes in the tube is 8 cm then the velocity of sound in metal will be (v = 332 m/s.)