Answer:
Explanation:
energy of photon having wavelength of 400 nm = 1237.5/400 eV
= 3.1 eV.
Maximum kinetic energy of photoelectrons = 1.1 eV .
Threshold energy Ф = 3.1 - 1.1 = 2 eV .
energy of photons having wavelength of 310 nm = 1237.5 / 310 eV = 4 eV .
Maximum kinetic energy of photoelectrons = energy of photons - Threshold energy
= 4 - 2 = 2 eV .
Required kinetic energy K₀= 2 eV.
The temperature of the air is -27°C
<u>Explanation:</u>
Given:
Frequency (f)=620 Hz
Wavelength (λ)=0.5 m
To Find:
Temperature of air = ?
Formula to be used:
Solution:
velocity at the current temperature v=fλ
Temperature of the air is given by the expression
Thus the temperature of the air is -27°C
When water changes into vapor, it is called evaporation. BONUS: This is formed by the boiling point of water, which is 230°F (Fahrenheit) or 110°C (Celsius).
A convex mirror of focal length 10 cm forms an upright and magnified image of a real object placed at a distance of 20 cm from the mirror. A concave lens causes light to diverge. A concave mirror can produce either real or virtual images. ... The images produced by a convex mirror are smaller than the object it reflects.
