Answer:
a) -41.1 Joule
b) 108.38 Kelvin
Explanation:
Pressure = P = 290 Pa
Initial volume of gas = V₁ = 0.62 m³
Final volume of gas = V₂ = 0.21 m³
Initial temperature of gas = T₁ = 320 K
Heat loss = Q = -160 J
Work done = PΔV
⇒Work done = 290×(0.21-0.62)
⇒Work done = -118.9 J
a) Change in internal energy = Heat - Work
ΔU = -160 -(-118.9)
⇒ΔU = -41.1 J
∴ Change in internal energy is -41.1 J
b) V₁/V₂ = T₁/T₂
⇒T₂ = T₁V₂/V₁
⇒T₂ = 320×0.21/0.62
⇒T₂ = 108.38 K
∴ Final temperature of the gas is 108.38 Kelvin
A) 
The energy of an x-ray photon used for single dental x-rays is
The energy of a photon is related to its wavelength by the equation
where
is the Planck constant
is the speed of light
is the wavelength
Re-arranging the equation for the wavelength, we find
B) 
The energy of an x-ray photon used in microtomography is 2.5 times greater than the energy of the photon used in part A), so its energy is
And so, by using the same formula we used in part A), we can calculate the corresponding wavelength:
To do this we may use things that are good conductors - are painted dull black -
Have a air flow around them Maximised.
The sun light that received by the water in the ocean will increase the average temperature of the water and make it warmer.
With the help of wind and current, the warm water will spread out to another region, and increasing the average temperature in that region and affecting its overall climate.
Example The temperature rise in Valdivia<span>, Chile and in Beijing, China after receiving warm water from arctic.</span>
