Question
A thief is spotted by a policeman from 500 m. When the
policeman starts chase, the thief also starts running. Assuming that the speed of the thief is 10 km/h and that of the policeman is 12.5 km/h. How far will the thief run before he is caught?Solution
Speed of thief =10km/h =10Γ5/18=25/9m/s The relative speed of the thief and the policeman = 12.5 - 10 = 2.5 km/h or 2.5(5/18) = (25/36) m/s Time taken by the policeman to catch the thief. T = 500/ (25/36) T=36Γ20 = 720 s Now Distance traveled by the thief before getting caught. Β D = 25/9Γ 720= D = 25 x 40 = 2000 m or 2 km The thief ran 2 km before he is caught.
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