A pebble is dropped from the edge of a cliff 45m high. Neglect air resistance.
(a) Calculate the time taken by the pebble to reach the ground. Take g=9.8ms−2.
(b) Determine the magnitude of its velocity just before impact.
(c) If another student uses g=10ms−2 for the same calculation, find the percentage error introduced in the value of time obtained in part (a).