Final answer:
To protect the pharmacy counter, a barrier's height can be determined using the equations of motion, considering the projectile motion of objects thrown towards the counter.
Step-by-step explanation:
To determine the height of a barrier required to protect the pharmacy counter, we need to consider the projectile motion of objects thrown towards the counter. One way to calculate the necessary height is using the equations of motion. We can use the equation h = (v^2 * sin^2(θ))/(2g), where h is the height, v is the initial velocity, θ is the angle of projection, and g is the acceleration due to gravity.
For example, if a projectile is thrown with an initial velocity of 20 m/s at an angle of 45 degrees, we can substitute the values into the equation to find the required height. Assuming the acceleration due to gravity is 9.8 m/s^2, the calculation becomes h = (20^2 * sin^2(45))/(2 * 9.8) = 2.04 meters.
Therefore, a barrier at least 2.04 meters tall would be required to protect the pharmacy counter.