How would the photographer use the polarizing filter to find out the direction of polarization of the light coming from the blue sky?

by rotating the filter                    

Explanation:

Rayleigh's scattering is given by the process of the scattering of light by molecules. This is very important physical phenomenon. Polarization is also an effect of light scattering.

A photographer wishes to capture photos of some cloud formation by using the polarizing filter. So the photographer will have to rotate the polarizing filter until the intensity of the light becomes maximum such that the light polarization is acts along the axis of the filter.

answer: the correct answer is 1.

explanation: there are various process in which a radioactive nuclei decays:

1) alpha decay: in this process, a heavier nuclei decays into lighter nuclei by releasing alpha particle. the mass number is reduced by 4 units.

2) electron capture: in this decay process, a parent nuclei absorbs an electron and gets converted into a neutron. simply, a proton and an electron combines together to form a neutron. mass number does not change in this process.

3) gamma ray emission: it is a decay process in which an unstable nuclei gives excess energy by a spontaneous electromagnetic process. this decay releases . this process does not change the mass number.

4) positron emission: it is a type of decay process, in which a proton gets converted to neutron and an electron neutrino. this is also known as -decay. in this the mass number remains same.

from the above information, we see that only alpha-decay is producing a change in the mass number of the nucleus.