A projectile is shot from the ground at an angle of #pi/6 # and a speed of #5 m/s#. When the projectile is at its maximum height, what will its distance, factoring in height and horizontal distance, from the starting point be?

1 Answer
May 18, 2017

dx=0,22 m dy=0,9566

Explanation:

https://www.ilephysique.net/physique_terminale-mouvement-projectile-champ-pesanteur.php

We have to calculate the initial speed in x and in y:
#V_(0x)=V_ocos(theta)=(5)cos(pi/6)=sqrt(3)/2#
#V_(0y)=V_osin(theta)=(5)sin(pi/6)=2.5#

Let's calculate the distance in y (height):

We have to know when is the projectile at its maximum height. Let's use the equation of the speed for an object with acceleration:
#V_y=V_(0y)+aDeltat#

The acceleration is #-9.8m/s^2# because of earth's gravity:
#0=2.5+(-9.8)Deltat => Deltat=2.5/9.8#

To find the distance in y we have to use the equation of distance:
#y=y_(0)+v_(0y)t+1/2 at^2#
#=> y= (2.5)(2.5/9.8)+(1/2)(-9.8)(2.5/9.8)^2#
#=> y~~0.9566m#

To find the distance in x we have to use another time the equation of distance (this time there's no acceleration):
#x=x_(0)+v_(0x)t+1/2 at^2#
#=> x= (sqrt(3)/2)(2.5/9.8)#
#=> x~~0.22m#