TOMMY FLIPS A MARBLE INTO THE AIR. ITS INITIAL VELOCITY IS 8.0 m/s.
TAKING g = 10 m/s2 AND IGNORING AIR RESISTANCE, CALCULATE (i) THE MAXIMUM HEIGHT, h, THE MARBLE REACHES, (ii) THE VELOCITY OF THE MARBLE ON RETURNING TO HIS HAND, (iii) THE TIME THAT THE MARBLE IS IN THE AIR.
(i) Maximum height, h = (initial velocity)2 / (2 x acceleration due to gravity)
h = (8.0 m/s)2 / (2 x 10 m/s2)
h = 32 m
(ii) Velocity of the marble on returning to his hand = -8.0 m/s
(iii) Time that the marble is in the air = (2 x initial velocity) / acceleration due to gravity
Time = (2 x 8.0 m/s) / 10 m/s2
Time = 1.6 s