A super ball bounces by 2
3
of its initial bounce when
dropped on a hard surface. If it is dropped from a
height of βππ.
29. After what bounce would the ball have
travelled a total distance of 2.74βππ
A. 4
B. 5
C. 6
D. β
The total distance travelled by the ball after π bounces can be calculated using the formula:
total distance = πβ + 2(πβ1)πβ
where π=23 is the fraction of the initial height reached after each bounce.
So, we need to find the value of π for which the total distance is 2.74β.
2.74β = πβ + 2(πβ1)πβ
Simplifying and solving for π, we get:
π = 3.74/0.69 β 5.42
Therefore, the ball would have travelled a total distance of 2.74β after the 5th bounce.
Answer: B. 5
To determine the answer, we need to find the total distance traveled by the ball after each bounce.
Given that the ball bounces by 2/3 of its initial bounce height, we can calculate the distance traveled in each bounce as follows:
Distance after the first bounce = 2/3 * βππ
Distance after the second bounce = 2/3 * (2/3 * βππ)
Distance after the third bounce = 2/3 * (2/3 * (2/3 * βππ))
We can see that for each successive bounce, the distance traveled is 2/3 of the previous distance traveled.
Now, let's calculate the total distance traveled after each bounce:
Total distance after the first bounce = Distance after the first bounce
Total distance after the second bounce = Distance after the first bounce + Distance after the second bounce
Total distance after the third bounce = Distance after the first bounce + Distance after the second bounce + Distance after the third bounce
Simplifying these equations, we have:
Total distance after the first bounce = 2/3 * βππ
Total distance after the second bounce = 2/3 * βππ + 2/3 * (2/3 * βππ)
Total distance after the third bounce = 2/3 * βππ + 2/3 * (2/3 * βππ) + 2/3 * (2/3 * (2/3 * βππ))
Now, let's calculate the total distance after each bounce:
Total distance after the first bounce = 2/3 * βππ = (2/3)βππ
Total distance after the second bounce = (2/3)βππ + (2/3)(2/3)βππ = (2/3)βππ + (4/9)βππ
Total distance after the third bounce = (2/3)βππ + (4/9)βππ + (8/27)βππ = (2/3)βππ + (4/9)βππ + (8/27)βππ
From the given information, we are looking for the bounce at which the total distance traveled is 2.74βππ.
Comparing the total distances after each bounce to 2.74βππ, we find that the total distance after the third bounce is the closest match.
Therefore, the answer is option C. 6