Answer:
λ = hv
If frequency is doubled :
λ = h × 2v
λ = 2hv
Thus wavelength is doubled
plane is flying at an altitude of 70 m
now if an object is dropped from it then time taken by object to drop on ground will be given as
here initial speed in vertical direction must be zero as plane is moving horizontal
given that
y = 70 m
a = 9.8 m/s^2
now since the plane is moving horizontally with speed v = 44 m/s
so the horizontal distance moved by the object will be
so the distance moved by the box is 166.3 m