Aspecial standard weight, known to weight 10 n to high accuracy, is used to check the accuracy of two spring scales. on the first scale the weight gives a reading of 8.4 n. on the second scale the weight gives a reading of 9.1 n. the percent difference between the measurements of the two scales is %. (never negative.)

16 % and 9 %

Explanation:

Accurate reading = 10 N

reading of first balance = 8.4 N

reading of second balance = 9.1 N

Percentage difference in first reading

=

= = 16 %

Percentage difference in second reading

=

= = 9 %

answer: what are you talking about?

explanation:

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.