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Darya [45]
3 years ago
6

a body starts from rest and moving under uniform acceleration of 4 metre per second square travel half of its total path during

last second of its motion find the time and total distance ​
Physics
1 answer:
lakkis [162]3 years ago
5 0

Answer:

t = 3.414 s

s = 23.3 m

Explanation:

Let t be the total time of motion

Let s be the total distance of motion

s - s/2 = ½at² - ½a(t - 1²) = ½a(t² - (t - 1)²)

s/2 = ½a(t² - (t² - 2t + 1)) = ½a(t² - t² + 2t - 1)

s = a(2t - 1)

s = 4(2t - 1)

s = 8t - 4

8t - 4 = ½4t²

8t - 4 = 2t²

0 = 2t² - 8t + 4

0 = t² - 4t + 2

t = (4 ±√(4² - 4(1)(2))) / 2 = (4 ± √8)/2 = 2 ± √2

t = 3.414 s

or

t = 0.5857... s which we ignore because it does not have a full last second.

s = ½(4)3.414² = 23.3137... 23.3 m

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