A spring gun is used to project a 0.5 kg ball, in order to perform this experiment the spring was initially

compressed by 0.005 m. Find the ball’s speed when it leaves the gun, if the spring constant is 395 N/m.

Explanation:

Given that,

Mass of ball M = 0.5kg

Spring compressed x = 0.005m

Spring constant K = 395N/m

Speed of ball?

Using conservation of energy

Energy stored in the spring is equal to the kinetic energy of the ball

U = K.E

½kx² = ½mv²

½ × 395 × 0.005² = ½ × 0.5 × v²

4.9375 × 10^-3 = 0.25v²

v² = 4.9375×10^-3 / 0.25

v² = 0.01975

v =√0.01975

v = 0.14m/s

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.

electrical power