Answer:
11.515 Joule
Explanation:
Volume of aluminium = V = 4.89×10⁻³ m³
Coefficient of volume expansion for aluminum = α = 69×10⁻⁶ /°C
Initial temperature = 19.1°C
Final temperature = 357°C
Pressure of air = 1.01×10⁵ Pa
Change in temperature = ΔT= 357-19.1 = 337.9 °C
Change in volume
ΔV = αVΔT
⇒ΔV = 69×10⁻⁶×4.89×10⁻³×337.9
⇒ΔV = 114010.839×10⁻⁹ m³
Work done
W = PΔV
⇒W = 1.01×10⁵×114010.839×10⁻⁹
⇒W = 11.515 J
∴ Work is done by the expanding aluminum is 11.515 Joule
Answer:
c. 0.25km
Explanation:
v=f x wavelength
3000 = 12 x wavelength
wavelength = 3000/12 = 250m
250m to km
To convert m to km, we divide by 1000
250/1000 =0.25km
wavelength = 0.25km
La respuesta es la letra b