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 simplest arrangement of a reflex arc consists of the receptor, an interneuron (or adjustor), and an effector; together, these units form a functional group. Sensory cells carry input from the receptor (afferent impulses) to a central interneuron, which makes contact with a motor neuron.
Here 1 kg mass is hold against compressed spring
when it is released and reached to natural position it will start moving with certain speed
As per energy concept we will now say that potential energy stored in the spring will convert into kinetic energy of the block
so here we will say




so block will released with speed 2.145 m/s