During the phase transition vapour --> liquid water, the temperature of the water does not change; the molecules of water release heat and the amounf of heat released is equal to

where
m is the mass of the water

is the latent heat of evaporation.
For water, the latent heat of evaporation is

, while the mass of the water is

so, the amount of heat released in the process is
Answer:
(a) 5.04 eV (B) 248.14 nm (c) 
Explanation:
We have given Wavelength of the light \lambda = 240 nm
According to plank's rule ,energy of light


Maximum KE of emitted electron i= 0.17 eV
Part( A) Using Einstien's equation
, here
is work function.
= 5.21 eV-0.17 eV = 5.04 eV
Part( B) We have to find cutoff wavelength



Part (C) In this part we have to find the cutoff frequency

Answer:

Explanation:
As we know that amplitude of forced oscillation is given as

here we know that natural frequency of the oscillation is given as

here mass of the object is given as



angular frequency of applied force is given as


now we have


Given,
A player kicks a soccer hits at an angle of 30° at a speed of 26 m/s
We can resolute the trajectory of soccer into horizontal and vertical components.(Please see the attached file)
We can have,
Horizontal velocity component of ball= 26cos(30°) = 26×(√3÷2) = 22.51 m/s
And vertical velocity component of ball = 26sin(26°) = 26×(1÷2) = 13 m/s
B-things that can attract iron.