A Level New Curriculum Physics Sv Topic 4 Motion Under Gravity

Please find free notes, tests and marking guides of physics, chemistry, biology and mathematics from: digitalteachers.co.ug P a g e | 1 SENIOR FIVE TERM 1 TOPIC 4/6: MOTION UNDER GRAVITY Competency: The learner investigates the effect of force on bodies moving under gravity and the applications of this phenomenon Motion under gravity In absence of any resistance, all bodies regardless of their mass fall with same acceleration near the earth’s surface. Acceleration due to gravity is the rate of change of velocity for freely falling body and it is symbolized as g. g = 9.81ms2 and it replaces “a” in equation of motion For a body falling under gravity, g is positive and g is negative for the object moving upwards. Example 1 A ball is thro wn vertically upw ards with initial speed 20m s-1. After reaching the maximum hei ght and on the way down it strik es a bird 10m above the ground. (a) Calculate the highest point reached u = 20ms-1, g = -9.8ms-1, v = 0 from v2 = u2 + 2as 0 = 202 + 2 x -9.8 x s The highest distance, s = 20.4m (b) Calculate the speed at which it strike the bird u = 0, s = (20.4 -10) = 10.4m, g = 9.8ms-2 From v2 = u2 + 2as v2 = 02 + 2 x 9.8 x 10.4 v = 14.3ms-1 Example 2 A stone is thro wn vertically upwards with a speed of 10m s-1 from a building. If it tak es 2.5 se conds to reach the ground, find the height of the building. Solution Please find free notes, tests and marking guides of physics, chemistry, biology and mathematics from: digitalteachers.co.ug P a g e | 2 Time taken to move from A to B v …