Physics question, me? which applied force will allow a 25 newton block of steel to continue sliding on a steel table? the block of steel has a kinetic coefficient of friction of 0.57 and a static coefficient of friction of 0.74. a) 3.5 n b) 7.0 n c) 14.0 n d) 18.0 n

As we know that block of steel is continue to be in moving state

so here the friction must be kinetic friction between two surface

so we know that formula of kinetic friction must be

now we have

now from the above equation we have

So here we need atleast 14.25 N force to continue sliding the box now as per given options all forces which are less than 14.25 N is not correct

Hence correct answer must be 18.0 N

D)18.0 N

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.