Q1 ours does 15625 lines per second I think, that is for the old crt system. I do not have the slightest Idea what the digital lcd system does. That is 25 FPS x 625 lines per frame. Q2 3.3333 Q3 8 Q4 It is the Width of slit in mm/speed of the shutter in mm/sec Q5 I would put the focal plane shutter of the film camera on 1/15 sec and move the camera during the exposure at a known rate of k mm/sec then using distance from focal plane to light/distance of lens from focal plane = m then the distance between two bright lines parallel to the direction of movement is equal to mk seconds. So the flashing rate is 1/mk Q6 DISTANCE MOVED IN METERS IN ONE SECOND GIVES VELOCITY IN METERS PER SECOND. Q7 Because the object moves as the slit travels across the film so the start of the slits travel is exposed before the end of its travel giving a sloping image of a moving object. Q8 Because the object moves during the exposure time outside the width of the film. This means the total movement is outside measurement range and the velocity is unknown but greater than observed length of blur x shutter speed. Q9 because it is only exposed as its light hits the film. Q10 The object travelled one foot in 1/100 second so the velocity was 100 feet per second. Q11 I do not know. Q12 According to Galileo they just do as they are pulled by the Earth's gravity and accelerate at the rate of 32 feet/sec/sec. I do not have a clue why! Q13 10 feet Q14 1200 rpm Q15 20 fps Q16 0.000001 Q17 True because one counts the number of revolutions over the exposure time (n) and then use n/shutter speed x 60 to give rpm. Q18 True because the movement velocity on the film is reduced because the magnification is lower. Q19 This question is incorrectly stated. The power is in watts which is joules per second so the power of a flash is the total energy (Joules) divided by the flash time in seconds or Energy x speed of flash. Joules is watt seconds. Q20 the width of the blur must be less or equal to the circle of confusion as seen by the human eye at the viewing distance used. Q21 I have no idea Q22 700 miles/hour Q23 The duration of the flash is reduced but the power output is the same, however the energy output is reduced. Q24 The duration of the flash is controlled by a thyratron (or semiconductor equivalent) and so is the same but the power is increased making the energy greater. Probably twice as much. Q25 1/ Velocity of sound in feet/second. =2.7 E-7 seconds or 0.00000027 sec Q26 1/e x peak power where e is the base of Naperian logarithms Q27 The bullet is moving to the right and the power of the flash faded during it flight. Q28 A device to measure the time between two events. Q29 1.2 seconds between exposure. Q30 3000 frames/second Q31 10 Q32 He used high speed photography to photograph the movement of horses legs proving that a galloping horses hooves all left the ground together for a short time. Q33 1 frame rate 2 exposure time 3 aperture Q34 Exposure time Q35 1000 Q36 Ker Cell to make for short exposure time. Q37 Don't know but probably by starting to record before the event of interest. Q38 I cannot answer this question because I do not know what a foot-candle is nor the meaning of sensitivity of 100 ISO. Don't quote me! Chris -----Original Message----- From: owner-photoforum@xxxxxxxxxxxxxxxxxx [mailto:owner-photoforum@xxxxxxxxxxxxxxxxxx] On Behalf Of ADavidhazy Sent: 16 January 2011 16:13 To: List for Photo/Imaging Educators - Professionals - Students Subject: Sample exam for your amusement It is midterm exam time again and so if you'd like to see if you can figure out answers to questions never before having beforehand heard the answers (Reminiscent of Karnak the magnificent?) this link takes you to a sample exam covering 5 weeks in which standards, shutter calibration, velocity and rotation rate measurements, electronic flash concepts and intro to time lapse and high speed imaging were discussed/ covered. http://people.rit.edu/andpph/text-exam-sample-high-speed-2010.html ;) Andy
