Which of the following statements about a conductor in electrostatic equilibrium is false?
(a) the electric field inside the conductor is zero.
(b) just outside the conductor, the electrostatic field is perpendicular to its surface.
(c) the net charge inside the conductor is zero, all excess charge resides on the surface.
(d) a charge located within a hole in a conductor at equilibrium feels no force from charges outside the conductor.

All the options are correct

Explanation:

From the properties of the conductors when it is in the electrostatic equilibrium, all the given options in this problems are correct.

The option (A). is correct. This is so because the electric field inside the conductor is proportional to the negative of the gradient of the potential energy. For equilibrium potential should be minimum, therefore electric field is zero.

The option (B). is correct. This is due to achieving the static equilibrium of the surface, electric field should be perpendicular to its surface.

The option (C). is also correct. This is due to attaining static equilibrium, the charges inside the conductor should not be moving. Therefore the net charges should be zero inside the conductor.

The option (D). is correct. This is because for achieving electrostatic equilibrium, the charges inside the conductor should not moving, for this the net force experienced by the charges inside the conductor by the charges outside the conductor is zero.

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.

c because the action was the roller coaster reaches bottom of hill (action) reaction would be blood tends to drain away from head

hope this !