You and a friend work in buildings six equal-length blocks apart, and you plan to meet for lunch. your friend strolls leisurely at 1.2 m/s, while you like a brisker pace of 1.7 m/s . knowing this, you pick a restaurant between the two buildings at which you and your friend will arrive at the same instant if both of you leave your respective buildings at the same instant?

3.51724 blocks

2.48275 blocks

Explanation:

L = Length of one block

t = Time taken by both person

Distance that I walk

The Distance that I will walk is 3.51724 blocks

Distance my friend will walk

Distance my friend will walk is 2.48275 blocks

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.