Atomic and Nuclear Physics Answers

A student is asked to use a computer simulation of radioactive decay. The sample chosen has a half-life of 2.5 hours and contains 38400 isotopes of radioactive material. Calculate the number of unstable nuclei remaining after 12.5 hours.

A teacher decides to determine the count rate of a radioactive sample stored at school. Her reading show that there are 240 counts in a time of two minutes. Calculate the count rate of the radioactive sample, including a suitable unit.

2.274 MeV represents the maximum energy of the energetic particle released in a decay from yttrium-90 directly to the ground state of zirconium-90. Which of the following statements is correct?

a) All of the energetic particles produced in this transition have the same energy and this energy is equal to the maximum energy value

b)The energetic particles have a range of energies. This is because some energy is converted to the mass of an electron and this may or may not happen during the decay.

c) The energetic particles have a range of energies. This is because extra energy can be released if a positron encounters an electron which may or may not happen during the decay

d)The energetic particles have a range of energies. This is because some energy is carried away by a neutrino and the amount carried by the neutrino varies.

you are studying high energy particles produced by a radioactive decay process. The particles are directed through a region of an electric field and it is found that they do not deflect. The particle could be:

i) An alpha particle ii) A beta-plus particle iii) A beta-minus particle iv) a photon v) a neutrino

a) i

b) i, ii and iii

c) iv

d) v

e) iv and v 

Define light wave

What was the force being applied by the pitcher's hand if the ball is in contact with it for 0.2s?

A soccer ball of mass 0.50 kg, initially at rest, is kicked by a force of magnitude 1200 N that lasts for 15 milliseconds. 

What is the velocity of the ball after the kick? 

A 50kg cat statue falls from a second floor (10m high) window. With what momentum does it impact the ground with?

A 50kg cat statue falls from a second floor (10m high) window. With what momentum does it impact the ground with?

 In a radial electrostatic filter, find the field strength in Volts per centimeter, necessary to bend

singly ionized atomic Oxygen ions in an arc having a 25 cm radius if the ions have fallen through

a potential difference of 20 000 V before entering the filter.