- Explain the basic radiation characteristics of x-ray beam quality,quantity and intensity (kVps , mAs) r
- Why is it rare to see a solar eclipse? Only a people in the small solar eclipse shadow can see the eclipse. It only happens in the middle of the night. Solar eclipses do not occur very often on Earth. Most people don 't have the right glasses.
- Why does the moon look "reddish" during a total lunar eclipse? refraction of light from the Earth 's atmosphere reflection of light from the sun reflection of light from the Earth's atmosphere refraction of light from the sun
- (6 marks) QUESTION TWO (15 Marks) (a) A particle moves along the curve x=t, y=t^2 and z=t^3 where t is the time. Find the components of its velocity and acceleration at time t=1 (b) The acceleration of a particle is given by (5 marks) (d^2overrightarrow (r))/(dt^2)=(3cos(3t))hat (i)+(3sin(3t))hat (j)+that (k) If overrightarrow (V) is zero at t=0 , find overrightarrow (V) at any time. (5 marks) (c) Find the angle between A=2i+2j-k and
- 18. The magnitude of the acceleration of an object at the top of its path is equal to Mark only one oval. in vertical velocity it horizontal velocity 0m/s 9.8m/s/s 19. The vertical velocity of an object at the top of its path is equal to Mark only one oval. it vertical velocity it horizontal velocity 0m/s 9.8m/s/s 5 points
