You accidentally drop a quarter into the hot coals of a campfire. You fish out the hot quarter with a pair of pliers and drop the quarter directly on top of a large 2 kg block of ice to cool it down. In what direction does heat flow:

There is no heat flow.
From the quarter to the block of ice

from the quarter to the block of ice

Explanation:

Heat flows from higher temperature to lower temperature until temperature of both bodies are in Equilibrium .

Since block of ice has lower temperature than that of quarter. heat transfer will take from quarter to ice until both have same temperature(in other words temperature are in Equilibrium for quarter and ice)

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.

prolly a beacuse the momentuem the car has increases while going down hill