Daryl ties a rope to a brick and lifts the brick straight up. the free body diagram below shows the brick when it is suspended above the ground. what is force 1 in this diagram

C. Tension

Explanation:

The tension in the cord occurs because of the muscle power of Daryl, who lifts the brick. While doing so, Daryl needs to overcome the gravitational pull on the brick.

EXTRA:

If the brick was much heavier, than Daryl's muscles would not be able to overcome the the gravitational pull on that brick, and then the much heavier brick would remain stationary on the ground, despite the efforts made by Daryl.

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.