1
JEE Main 2023 (Online) 25th January Morning Shift
Numerical
+4
-1

The distance between two consecutive points with phase difference of 60$$^\circ$$ in a wave of frequency 500 Hz is 6.0 m. The velocity with which wave is travelling is __________ km/s

2
JEE Main 2022 (Online) 28th July Morning Shift
Numerical
+4
-1
Out of Syllabus

The frequency of echo will be __________ Hz if the train blowing a whistle of frequency 320 Hz is moving with a velocity of 36 km/h towards a hill from which an echo is heard by the train driver. Velocity of sound in air is 330 m/s.

3
JEE Main 2022 (Online) 27th July Evening Shift
Numerical
+4
-1

A wire of length 30 cm, stretched between rigid supports, has it's nth and (n + 1)th harmonics at 400 Hz and 450 Hz, respectively. If tension in the string is 2700 N, it's linear mass density is ____________ kg/m.

4
JEE Main 2022 (Online) 26th July Morning Shift
Numerical
+4
-1
Out of Syllabus

When a car is approaching the observer, the frequency of horn is $$100 \mathrm{~Hz}$$. After passing the observer, it is $$50 \mathrm{~Hz}$$. If the observer moves with the car, the frequency will be $$\frac{x}{3} \mathrm{~Hz}$$ where $$x=$$ ________________.