To calculate the mass of the fuel, we use the formula

Here, m is the mass of fuel, V is the volume of the fuel and its value is
and
is the density and its value of 0.821 g/mL.
Substituting these values in above relation, we get
Thus, the mass of the fuel 247 .94 kg.
Answer:

Explanation:
By Einstein's Equation of photoelectric effect we know that

here we know that
= energy of the photons incident on the metal
= minimum energy required to remove photons from metal
= kinetic energy of the electrons ejected out of the plate
now we know that it requires 351 nm wavelength of photons to just eject out the electrons
so we can say

here we know that

now we have

now by energy equation above when photon of 303 nm incident on the surface





Answer:
Lubrication is used to reduce friction. It is generally used for moving machine parts. The lubricants are the substances which are used to reduce the friction which acts between two surfaces in contact, between which relative motion can occur.
Answer:
6538.8 Angstrom
Explanation:
work function, w = 1.9 eV = 1.9 x 1.6 x 10^-19 J = 3.04 x 10^-19 J
Let the longest wavelength is λ.
W = h c / λ
λ = h c / W
λ = (6.626 x 10^-34 x 3 x 10^8) / (3.04 x 10^-19)
λ = 6.5388 x 10^-7 m = 6538.8 Angstrom
Thus, the longest wavelength is 6538.8 Angstrom.
I think trace 1 is ac and trace 2 if dc but i’m not sure what will happen when a higher frequency is added?