Answer:
5.15348 Beats/s
4.55 mm
Explanation:
= Velocity of sound = 342 m/s
= Velocity of sound = 346 m/s
= First frequency = 440 Hz
Frequency is given by

Beat frequency is given by

Beat frequency is 5.15348 Hz
Wavelength is given by

Relation between length of the flute and wavelength is

At v = 346 m/s


Difference in length is

It extends to 4.55 mm
Answer:
B. The number of electrons emitted from the metal per second increases.
Explanation:
Light consists of photons . Energy of each photon depends upon frequency of light . The increase in intensity increases the number of photons . It does not increase energy of photons .
So if a high intensity light falls on a photosensitive plate , each photon ejects one electron . So number of electrons increases if we increase intensity of photon. It does not increase kinetic energy of ejected electrons . Work function depends upon the nature of plate.
velocity = distance / time v= d/t firstly you change 3000 m into km distance D = 3000/1000 = 3 km secondly time t = 21 min using velocity formula v = d/t = 3 km/21min =0.142km/min
Do find the percentage you:
5.43/15.6=0.34
Time by 100:
34%
Closest answer is 35%
Hope this helps ;)