Construction worker used 450 n of force to move materials 5 meters in 2 minutes.

how much power did the worker use?

a)
18.75 watts

b)
125 watts

c)
225 watts

d)
1125 watts

A. 18.75Watts

Explanation:

Power is defined as the rate of change of work done by a body. It is measures in Nms-¹ or watts.

Mathematically,

Power = Work done/time taken

Workdone = Force × distance moved in a specified direction.

Also note that the time must be in seconds being the standard unit.

Given Force = 450N

Distance = 5m

Time = 2minutes = 2 × 60 = 120seconds

Since Power = F × d/t

Power = 450 ×5/120

Power = 18.75 watts.

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.