Answer:
answer is option (c) child labour
Answer:
9.6 km/h
Explanation:
20 minutes=1/3 minute.
The speed of the bicycle: 3.2:1/3=9.6 km/h.
Answer: 9.6 km/h
Answer:
No ejection of photo electron takes place.
Explanation:
When a photon of suitable energy falls on cathode, then the photoelectrons is emitted from the cathode. This phenomenon is called photo electric effect.
The minimum energy required to just eject an electron is called work function.
The photo electric equation is
E = W + KE
where, E is the incident energy, W is the work function and KE is the kinetic energy.
W = h f
where. h is the Plank's constant and f is the threshold frequency.
Now, when the violet light is falling, no electrons is ejected. When the red light is falling, whose frequency is less than the violet light, then again no photo electron is ejected from the metal surface.
The answer more than likely based on research would be (B.)
