Answer:
9.8 m/s²
Explanation:
Fill in the blanks with the numbers from the diagram.
[tex]\text{average acceleration}=\dfrac{\text{final velocity - initial velocity}}{\text{time it takes to change velocity}}\\\\\text{average acceleration}=\dfrac{39.2\text{ m/s}-9.8\text{ m/s}}{3\text{ s}}=\dfrac{29.4}{3}\text{ m/s$^2$}\\\\\boxed{\text{average acceleration}=9.8\text{ m/s$^2$}}[/tex]
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You are told to start with t = 1 second and end at t = 4 seconds, so the elapsed time for which you're computing the acceleration is 4-1 = 3 seconds.
When you fill in your blanks, you probably want to put numbers only. I like to show the units in physics problems, just to make sure the math is right.
