Occurs when an energy source transfers heat directly to another object through space; an example would be an object becoming warm by sitting in the sunshine. a. conduction c. convection b. radiation d. heat select the best answer from the choices provided a b c d

b. radiation

Explanation:

In order to answer correctly, let's describe the three method of transfer of heat:

1) Conduction: conduction occurs when heat is transferred through two materials which are directly in contact with each other. The transfer of heat occurs because the kinetic energy of the particles in the first medium is transferred through collisions to the particles in the second medium. Conduction can occurs in solids, liquids and gases, but it cannot occur in empty space

2) Convection: convection occurs when a fluid is heated by an external source. In this case, the particles of the fluid closer to the source of heat are heated faster, therefore the area of fluid near the source becomes warmer and less dense, therefore rises and it is replaced by the colder parts of the fluid, and so on, creating a convection current. Convection occurs only in fluids (liquids or gases)

3) Radiation: radiation occurs when a source emits electromagnetic radiation, which carries energy through space and materials. Therefore, radiation can also occur in empty space.

Therefore, the example described:

an energy source transfers heat directly to another object through space; an example would be an object becoming warm by sitting in the sunshine.

Is an example of heat transferred through radiation.

ill do it for 100, also this isnt 80 its 40

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.