Which of these objects could be falling with constant acceleration?
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Answer:
1 and 2
Explanation:
If an object has constant acceleration, it's displacement at time t is:
Δx = v₀ t + ½ at²
For object 1:
0.44 = (0) (0.3) + ½ a (0.3)²
a = 9.78
3.14 = (0) (0.8) + ½ a (0.8)²
a = 9.81
So object 1's acceleration is approximately constant.
For object 2:
0.06 = (0) (0.3) + ½ a (0.3)²
a = 1.33
3.09 = (0) (2.1) + ½ a (2.1)²
a = 1.40
So object 2's acceleration is approximately constant.
For object 3:
0.44 = (0) (0.3) + ½ a (0.3)²
a = 9.78
3.09 = (0) (2.1) + ½ a (2.1)²
a = 1.40
So object 3's acceleration is not constant.