Q3. (a) The figure below shows a helium atorn. Electron Neutron Proton (1) Which one of the particles in the atom is not charged? Draw a ring around the correct answer, electron neutron proton (1) (il) Which two types of particle in the atom have the same mass? and (1) (ill) What is the atomic number of a helium atom? Draw a ring around the correct answer. 2 Give a reason for your answer. (2) (b) Alpha particles are one type of nuclear radiation. 1) Name one other type of nuclear radiation. (1)(il) Use the correct answer from the box to complete the sentence. electrons neutrons protons The difference between an alpha particle and a helium atom is that the alpha particle does not have any (1) (ili) Which one of the following is a property of alpha particles? Tick (V ) one box. Have a long range in air Are highly lonising Will pass through metals (1) (c) Doctors may use nuclear radiation to treat certain types of illness Treating an illness with radiation may also harm a patient. (i) Complete the following sentence. The risk from treating a patient with radiation is that the radiation may healthy body colls, (1) (il) Draw a ring around the correct answer to complete the sentence. Radiation may be used to treat a patient if the risk from the much bigger than radiation is about the same as the possible benefit of having the treatment. much smaller than (1)(b) Calculate the pulling force that is needed in the steel cable to keep the jib horizontal. Show clearly how you work out your answer. Pulling force = N