Stone A is projected vertically upwards at a speed of 12 m∙s-1 from a height h above the ground. Ignore the effects of air resistance.
3.1 Calculate the time taken for stone A to reach its maximum height. (3)
At the same instant that stone A is projected upwards, stone B is thrown vertically downwards from the same height at an unknown speed, v. Refer to the diagram below.
When stone A reaches its maximum height, the speed of stone B is 3v.
3.2 Calculate the speed, v, with which stone B is thrown downwards. (4)
At the instant stone A passes its initial position on its way down, stone B hits the ground.
3.3 Calculate the height h. (3)
3.4 Sketch velocity-time graphs for the complete motions of stones A and B on the same set of axes. Label your graphs for stones A and B clearly.
Show the following on the graphs:
• The time taken for stone A to reach its maximum height
• The velocity with which stone B is thrown downwards (4)
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