A pencil is dropped from the roof of the school. What is its speed after 3 seconds if down is the negative direction?

Hint: Use the equation for velocity under constant acceleration.

On Earth, the acceleration due to gravity is (-9.8 meters per second) per second.
If the school, the roof, and the pencil are on Earth, then after 3 seconds, the pencil's speed is
[ (-9.8 meters per second)/second ] times [ 3seconds ] = -29.4 meters per second

Answered by AL2006 | 2024-06-10

you have to use 1st equation of motion v = u +at as distance(s) is not given..... as pencil is dropped from rest therefore u = 0m/s and accleration due to gravity is = -9.8 m/s v = 0 - (9.8)(3) v = -29.4 m/s

Answered by hardikgupta | 2024-06-10

The pencil's speed after 3 seconds of free fall is 29.4 m/s downwards. This is calculated using the acceleration due to gravity, which is -9.8 m/s². The final velocity formula is applied to find this speed based on the time of fall.
;

Answered by AL2006 | 2025-05-16