\$1 Name: Kiran Status: other Age: 20s Location: N/A Country: N/A Date: 2000-2001 Question: Hi, I really appreciate the quick response. I have another question. Let us say there is no plank at all between the two supports. CAR ---> ------------ ------------ | | | | | | The car at high speed (Less than light speed of course) lets say 120 MPH ,would still cross the cliff (say a distance of 10 Meter)without falling. So whether there is plank or not,The car does not seem to put weight at all during that period.(And also the effect of Air is not so much as to believe that it is flying). (I guess Kinetic energy is responsible here,But was curious to know more in detail) What makes the car to cross the cliff without falling? And also as the speed of the car is increased the distance it crosses without falling also increases. Or in other words,Even when the car is moving with such a speed on ground,The weight on the ground should be lesser?? Replies: The vertical component of motion is independent of the horizontal component. So, for example, a bullet fired from a perfectly horizontal rifle 2 m above a perfectly level plane will hit the plane at exactly the same time as another bullet dropped from the same height at the instant the gun is fired. In the case of the car travelling at 120 mi/hr = 53 m/s (meters/second), it will cross the gap in a time t = d/v = 10 m/ (53 m/s) = 0.19s. In that time it will drop as far as any object released from rest. The equation is 2 2 2 1/2 g t = 0.5 32 ft/s (0.19 s) = 0.58 ft. = 7 inches! I strongly recommend that you do NOT try this! Best, Dick Plano... PS I hope this is not too late to be of any use... Dick Plano Click here to return to the Physics Archives

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