The acceleration due to gravity for any object, including 1 washer on the string, is always assumed to be m/s2

The value of acceleration due to gravity on all objects near the surface of earth will be 9.8 m/s/s or 10 m/s/s(approx)

Explanation:

here we know that all objects near the surface of earth will experience the force of gravity towards the center of earth.

this force of gravity is given as

now to find the acceleration due to this force we can say

here we will have

so acceleration due to gravity for all objects near the earth surface is nearly same or constant

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.