Answer: i)Pollen release and stigma receptivity do not occur at the same time. Either the pollen is released before the stigma is receptive, or the stigma is responsive long before the pollen is released.
(ii) The anther and stigma are positioned so that pollen does not come into touch with the stigma of the same flower.
(iii) Self-incompatibility, which prevents pollen germination and pollen tube formation in the same flower’s pistil or another blossom on the same plant.
(iv) Unisexual flower production Both autogamy and geitonogamy are prohibited by this circumstance.
.
)
west of the geographic north. The north tip of the magnetic needle of a dip circle placed in the plane of magnetic meridian points above the horizontal. The horizontal component of the earth’s field is measured to be 
Specify the direction and magnitude of the earth’s field at the location.At a certain location in Africa, a compass points 
and 
carrying currents of 
and 
in the same direction are separated by a distance of 
. Estimate the force on a 
section of wire A.
wire carrying a current of 
is placed inside a solenoid perpendicular to its axis. The magnetic field inside the solenoid is given to be 
. What is the magnetic force on the wire?
and making an angle of 
with the direction of a uniform magnetic field of 
. What is the magnitude of the field 
at a point 
from the wire?
-turns carrying current 
.
is at distance 
from the wire. Find the force acting on the electron if its velocity is directed towards the wire.