Choose the option that correctly answers and explains the question, "if the sum of the forces acting on an object equals zero, does this imply the object is at rest? " no, because the sum of the forces equaling zero only implies that the object is not accelerating. no, because even if the sum of the forces equals zero, it may have a nonzero component in one direction. yes, according to newton's second law, experiencing zero net force is the definition of being at rest. yes, because newton's first law implies that objects in motion must be acted on by a nonzero net force.

No, because the sum of the forces equaling zero only implies that the object is not accelerating.

Explanation:

When the sum of the forces acting on an object equals zero, this implies that the object is at equilibrium. And this could be either static or dynamic equilibrium.

A force is an agent that could change the state or direction of motion of an object. When the sum of all forces acting on an object equals zero, this implies all forces cancels out by resolution. Thus, the state of equilibrum is achieved. So this those not necessarily mean that the object is at rest, but could be in a dynamic equilibrium.

d

explanation:

i think the answer is d. but im not sure!

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.