Q2. Fill in the blanks: North Pole of a magnet will
.. North pole of another magnet.
South Pole of a magnet will.
North pole of a another magnet.
Needle of a compass lines up with the
of a magnet.
You can find the shape of a magnetic field using
and also a plotting.

repel , attract,l am sure with these two blanks only

Magnetic fields

A magnet creates a magnetic field around it. You cannot see a magnetic field, but you can observe its effects. A force is exerted on a magnetic material brought into a magnetic field. The force is a non-contact force because the magnet and the material do not have to touch each other.

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.

0.19 m/s and 0.45 m/s