Question

question 3 (1 point)
an object starts from rest and undergoes uniform acceleration. during the first second it travels 5.0 m. how far will it travel during the third second?
5.0 m
15 m
25 m
45 m

Explanation:

Step1: Find the acceleration

The displacement formula for an object starting from rest ($v_0 = 0$) is $s=\frac{1}{2}at^{2}$.
For $t = 1s$ and $s=5m$, we have $5=\frac{1}{2}a\times(1)^{2}$.
Solving for $a$ gives $a = 10m/s^{2}$.

Step2: Calculate the displacement in 3 seconds

Using $s=\frac{1}{2}at^{2}$ with $t = 3s$ and $a = 10m/s^{2}$, we get $s_3=\frac{1}{2}\times10\times(3)^{2}=45m$.

Step3: Calculate the displacement in 2 seconds

Using $s=\frac{1}{2}at^{2}$ with $t = 2s$ and $a = 10m/s^{2}$, we get $s_2=\frac{1}{2}\times10\times(2)^{2}=20m$.

Step4: Find the displacement in the third second

The displacement in the third second is $s = s_3 - s_2$.
Substituting the values, $s=45 - 20=25m$.

Answer:

25 m