John pushes his brother danny on a skateboard. john applies a force of 150 n and danny's acceleration is 1.2 m/s^2. what is the combined mass of danny and his skateboard

125 kg

To get this, use the equation F = ma (force = mass x acceleration)

150 = m * 1.2

150/1.2 = m

125 = m

divide the right side by the left side

0.024÷1.2=0.02 for example

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.