Test Preparation on JEE Mains Waves Paper (I)-2018

Length of a string tied to two rigid supports is 40 cm.
Maximum length (wavelength in cm) of a stationary wave
produced on it is

Tube A has both ends open while tube B has one end
closed, otherwise they are identical. The ratio of
fundamental frequency of tube A and B is [2002]

A tuning fork arrangement (pair) produces 4 beats/sec
with one fork of frequency 288 cps. A little wax is placed on
the unknown fork and it then produces 2 beats/sec. The
frequency of the unknown fork is [2002]

A wave y = α sin(ωt–kx) on a string meets with another
wave producing a node at x = 0. Then the equation of the
unknown wave is [2002]