Answer:
Vf = 15 m/s
Explanation:
First we consider the upward motion of ball to find the height reached by the ball. Using 3rd equation of motion:
2gh = Vf² - Vi²
where,
g = acceleration due to gravity = -9.8 m/s² (negative sign for upward motion)
h = height =?
Vf = Final Velocity = 0 m/s (Since, ball momentarily stops at highest point)
Vi = Initial Velocity = 15 m/s
Therefore,
2(-9.8 m/s²)h = (0 m/s)² - (15 m/s)²
h = (-225 m²/s²)/(-19.6 m/s²)
h = 11.47 m
Now, we consider downward motion:
2gh = Vf² - Vi²
where,
g = acceleration due to gravity = 9.8 m/s²
h = height = 11.47 m
Vf = Final Velocity = ?
Vi = Initial Velocity = 0 m/s
Therefore,
2(9.8 m/s²)(11.47 m) = Vf² - (0 m/s)²
Vf = √(224.812 m²/s²)
<u>Vf = 15 m/s</u>
Options are;
A: measuring cylinder, metre rule
B: measuring cylinder, stopwatch
C: metre rule, balance
D: metre rule, stopwatch
Answer:
A: measuring cylinder, metre rule
Explanation:
Usually, when measuring volume of a small material, we make use of a piece of laboratory apparatus known as measuring cylinder which is also known as graduated cylinder.
Since it is a graduated cylinder, it means we will make use of metre rule.
Thus, the correct option is option A.
B. changing the direction over which a force is exerted
