I have the below HW question:
What I've done is replace t with 2, thus obtaining that the ball is at a height of 1.25m after 2 seconds and hence, it will travel over the net. Am I correct?
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Statement 1 is wrong: The displacement after two seconds is $1.25$, as you stated when you plugged in $2$ into the original equation.
Statement 2 is wrong as well. Even if you plug in the correct number, you already plot height vs time. So the gradient will have units of m/s, therefore it's a velocity (average velocity in the vertical direction).
I am not sure how you concluded statement 4 from statement 3. If it started at 1.25, and you have a negative gradient, then the height should decrease.
Statement 4 is true, but you obtain it directly from the formula.
Andrei
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I think i mislead you in my question. Just posted a copy of the question. – Joann Sammut Jan 28 '20 at 16:50
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Yes. Your solution is correct. All you need is to plug in $t=2$ to get $h=1.25$ and note that it is greater than $1$. – Andrei Jan 28 '20 at 16:53