Question
The falling height of an object is directly proportional
to the square of the rime. An object falls 80 cm in 4 seconds. Then in 8 seconds, from how much height (in cm) will the object fall?Solution
The height fallen h is directly proportional to the square of the time t. The object falls 80 cm in 4 seconds. We need to find the height fallen in 8 seconds.  The relationship h proportional t² means that if we double the time, the height fallen will be quadrupled (since (2t) ² = 4t²).  Given that in 4 seconds the object falls 80 cm: In 8 seconds (which is twice the time), the object will fall: Height 4 x 80 =cm 320 cm Therefore, in 8 seconds, the object will fall from a height of 320 cm.
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