medscholhopeful

New Member
10+ Year Member
Apr 12, 2006
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Non-Student
there is an inclined plane diagram, if object m slides down the plane in 3s, what is the ratio of the distance it travels in the 1st second compares to the distance it travels in the 2nd second...seem easy enuf but still dont know how they got it.. this is my logic

using x=1/2at2, i divided x1/x2 = 1/2at2(for 1st second, t=1)/1/2at2(for second second t=2).. i came up with 1:4 but answer is 1:3 how come?.. thanks
 

ThirdEye

10+ Year Member
Apr 14, 2009
362
6
Status
Pre-Medical
Since it's a ratio, it will be the same ratio as if it was free falling for 3 sec.

After 1 second the velocity will be 10m/s and the avg. v is 5m/s... so it goes 5m in 1 sec.

After 2 seconds the velocity will be 20m/s. The avg v between 1 and 2 seconds is (10+20)/2 = 15m/s..... so it travels 15m from second 1 to second 2.

5:15 ----> 1:3