Find the magnitude of the magnetic field at a distance of 1.70 cm from a single long wire carrying a current of 23.3 A. (2) This part of the problem asks for something about an arbitrary long wire, rather than for something specifically described in this problem. To make a connection to the problem, the wire carries the same current as that in the rails in the problem statement. Notice also that a distance of 1.70 cm from one of the rails is the midpoint between the rails. Substitute numerical values into B = μ0I 2πr to find the magnitude of the magnetic field at the indicated distance from a long wire carrying the indicated current. Bwire = μ0I 2πr = (4π ✕ 10−7 T · m/A) A 2π m = ✕ 10−4 T

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.

compass can be used day and night, cloudy or sunny