BMAT Physics Skills Tested A quick summary in the order of the following questions on the main topics tested by BMAT. Newton’s laws, Graphs of Motion and Definitions F = ma Distance = area under a v‐t graph Acceleration = gradient of v‐t graph Connected things all move with the same acceleration (the train) Momentum Force x Time = change of momentum (mv) Work Energy Power Calculating KE and GPE Interchange of these e.g. when something falls, all its GPE turns into KE Power = E/t Work done = F x d (if d is in line with F) Knowing that work done is energy transferred: so when a force stops something, its energy is transferred away by a force working through a given distance Conservation of Energy when there is work done against friction Understanding that when KE and GPE interchange there might also be energy transferred into heat by friction; working out how much by using work done (Fxd). For example, something falling with friction: GPE lost = KE gained + heat loss; mgh = ½ mv2 + Fd Remembering in this that d is measured in the direction moved but h is measured vertically Motion with drag The idea of terminal velocity; in particular, that when you are going at that speed, the air resistance equals your weight. Note that with or without the parachute, it’s the same force. In free‐fall, that size of force comes from a high speed, small area; with the parachute open, the same force is caused by small speed, large area. (Hence in the graphs question the answer is A). Understanding that acceleration has nothing to do with your current motion; it tells you how your motion will change. Hence the acceleration when you open the parachute is upwards (slowing you down) while you are still actually moving downwards. Moments/levers Balanced moments Remembering that the d in moment = Fd has to be measured perpendicular to the force line. Muscle questions: fulcrum means pivot and is always at the joint; the muscles attach close to but not at the joint; the muscle force is called the effort. The hardest thing to spot is that the load is the way the external object pushes on the limb e.g. the floor pushes on the foot. Radioactivity Half life from data or graph Penetration to determine which radiation reaches which detectors Decay equations – working out atomic and mass numbers e.g. when radiation is emitted Waves Speed = distance/ time as usual for energy transmitted by the wave Reading graphs: period from time graphs and wavelength from distance ones v = f x lambda Refraction changes wavelength (and speed) but not frequency; frequency is determined by the vibrations of the source so can never change in transit. Blue bends best (and beta bends best in radiation, although it hasn’t been asked) Dc Circuits Ohm’s law and definitions for V and I Circuit rules especially parallel combinations and short circuits (or breaks). Two bits of AS physics would be useful extra learning: combining parallel resistors and the idea of potential at a point. For circuit changes especially short circuits and switches, try drawing the circuit how it effectively is before and after the change e.g. if a lamp blows, that part of the circuit is gone so re‐draw without it. Electrical power as VI, V2/R and I2R. Determine which thing is constant when they describe making a change and use the formula that has the constant thing and the thing you know in it. Pressure and Density Basic use of p=F/A and simple hydraulics Simple density of objects (possibly mixtures so check you understand proportion by mass or by volume) BMAT Physics Practice Booklet Newton’s laws, Graphs of Motion and Definitions 2006 2009 past paper 2009 past paper 2010 past paper Momentum Specimen 2005 2008 Work, Energy and Power 2003 2005 Specimen 2005 2009 past paper 2010 past paper 2013 past paper 2011 past paper 2012 past paper Conservation of Energy when there is work done against friction New specimen 14 repeat of 2011 past paper 2012 past paper 2010 past paper Motion with drag 2004 2008 New specimen 14 repeat of Specimen 2005 (itself a slight modification of 2003 – option Eadded) 2009 past paper Moments/levers 2003 2005 Undated ‘past paper’ – same as 2007 2004 2008 Undated ‘past paper’ – same as 2007 2003 Radioactivity 2010 past paper Undated ‘past paper’ – same as 2007 2011 past paper New specimen 14 – same as 2013 past paper Q15 2012 past paper 2003 2012 past paper 2004 2010 past paper 2005 2008 2006 2009 past paper 2005 2003 2008 Waves 2008 New specimen 14 same as 2010 past paper New specimen 14 same as 2012 past paper Undated ‘past paper’ – same as 2007 2003 2011 past paper 2009 past paper 2003 2006 2006 2005 2012 past paper 2011 past paper 2013 past paper 2013 past paper Heat Energy New specimen 14 Undated ‘past paper’ – same as 2007 Transformers New specimen 14 – same as 2007 (undated paper) Q7 (with MCQ options added) Specimen 2005 2003 – a one‐off on generators Electricity – dc circuits 2003 Specimen 2005 2010 past paper Specimen 2005 2011 past paper 2013 past paper 2008 2006 2013 past paper 2005 2004 2011 past paper 2012 past paper 2009 past paper 2006 2003 Pressure, Density etc. 2005 2013 past paper 2012 past paper Specimen 2005 2006 Other 2013 past paper 23 Consider this graph