Calculating Free Fall: Water Balloon Question | Math Homework Help

  • Thread starter Thread starter hershey1
  • Start date Start date
  • Tags Tags
    Fall Free fall
Click For Summary
SUMMARY

The discussion revolves around a physics problem involving the calculation of the trajectory of a water balloon dropped from a height of 18.0 meters. The student initially calculated the time of flight to be 3.3 seconds, leading to an incorrect conclusion that the balloon would not hit the professor. Upon further analysis, the correct time of flight was determined to be 0.82 seconds, indicating that the professor, walking at 0.450 m/s, would have moved only 0.37 meters during that time, thus avoiding a collision. The final conclusion is that the balloon comes within 18 cm of the professor, but this answer was initially marked incorrect.

PREREQUISITES
  • Understanding of kinematic equations, specifically y = v0t + 1/2gt^2
  • Basic knowledge of free fall motion and gravitational acceleration
  • Familiarity with unit conversions, particularly between meters and centimeters
  • Ability to perform calculations involving time, distance, and speed
NEXT STEPS
  • Review the derivation and application of kinematic equations in free fall scenarios
  • Study the effects of initial velocity on projectile motion
  • Learn about gravitational acceleration and its impact on falling objects
  • Practice similar physics problems involving motion and collision avoidance
USEFUL FOR

This discussion is beneficial for physics students, educators, and anyone interested in understanding the principles of projectile motion and free fall calculations.

hershey1
Messages
2
Reaction score
0

Homework Statement



A student at a window on the second floor of a dorm sees his math professor walking on the sidewalk beside the building. He drops a water balloon from 18.0 m above the ground when the prof is 1.00 m from the point directly beneath the window. The professor is 170 cm tall and walks at a rate of 0.450 m/s. How close does the balloon come to hitting the professor?

Homework Equations



y=v0t + 1/2gt^2

The Attempt at a Solution



I found the displacement to be 16.3 m from subtracting the distance of the building from the man's height. Using the formula, I calculated the time to be 3.3 seconds. This would say that the prof will not be hit by the water balloon since the prof would have walked only 82 cm by then. My answer was 18 cm but it was wrong.
 
Last edited:
Physics news on Phys.org
hershey1 said:

Homework Statement



A student at a window on the second floor of a dorm sees his math professor walking on the sidewalk beside the building. He drops a water balloon from 18.0 m above the ground when the prof is 1.00 m from the point directly beneath the window. The professor is 170 cm tall and walks at a rate of 0.450 m/s. How close does the balloon come to hitting the professor?

Homework Equations



y=v0t + 1/2gt^2

The Attempt at a Solution



I found the displacement to be 16.3 m from subtracting the distance of the building from the man's height. Using the formula, I calculated the time to be 0.82 seconds. This would say that the prof will not be hit by the water balloon. My answer was 18 cm but it was wrong.
Welcome to PF hershey1,

You may want to recheck your calculation of the flight time.
 

Similar threads

Replies
8
Views
4K
  • · Replies 11 ·
Replies
11
Views
2K
  • · Replies 20 ·
Replies
20
Views
5K
  • · Replies 2 ·
Replies
2
Views
7K
  • · Replies 5 ·
Replies
5
Views
6K
Replies
23
Views
4K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 3 ·
Replies
3
Views
5K
Replies
1
Views
8K