Missing part in the text of the problem:
"<span>Water is exposed to infrared radiation of wavelength 3.0×10^−6 m"</span>
First we can calculate the amount of energy needed to raise the temperature of the water, which is given by

where
m=1.8 g is the mass of the water

is the specific heat capacity of the water

is the increase in temperature.
Substituting the data, we find

We know that each photon carries an energy of

where h is the Planck constant and f the frequency of the photon. Using the wavelength, we can find the photon frequency:

So, the energy of a single photon of this frequency is

and the number of photons needed is the total energy needed divided by the energy of a single photon:
Answer:
1176 Nm or J
Explanation:
W = F*d
F = 60kg * 9.8 kgm/s^2 = 588 N
W = 588 N * 2m = 1176 N*m
Answer:
Explanation:
From the question we are told that mass
Thin layer radius 
Generally the expression for ths solution is given as
Xcm =(m*0 =m(-2R))/2m =-mR/(2m)=-R/2
the center of mass will not move at initial state
Considering the center of mass of both bodies


Therefore the enclosing layer moves
Distance= speed x time
distance = 2.6 m/s x 120s
distance= 312 meters
Answer:
When two forces acting on an object are equal in size but act in opposite directions, we say that they are balanced forces.
Explanation: