As a sample of water is heated, the energy is used to overcome the attractions between the molecules so that they begin to move past one
another. Then, the kinetic energy of its molecules increases. Which sections
of the heating curve illustrate this process?
200
150
D
100
A А
Temperature (°C)
50
с
0
7
-50
0
10
20
50
60
70
30 40
Time (min)
A. A followed by C
B. A followed by B
Ο Ο Ο Ο
C. C followed by B
D. B followed by C

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.

a sonic boom is a loud boom that breaks the sound barrier

explanation:

1.195000

explanation:

total mass=0.0117+0.0137+0.0881+0.0111

total mass= 0.01172kg

total velocity = 0.283-0.743+0.871-0.799+0.155+0.637+0.301=0.102

momentum=mv=0.1172*0.102=1.195000//