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A cannon ball is shot horizontally from a height of 4.9 m above the ground. The initial speed of the ball is 45 m/s. Neglecting friction, how long will it take the ball to hit the ground

User Kemakino
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Final answer:

The cannon ball shot horizontally will take 1 second to hit the ground. It is determined using the kinematic equation for free fall, considering the height of 4.9 meters and the acceleration due to gravity.

Step-by-step explanation:

The student is asking how long it will take for a cannon ball to hit the ground when shot horizontally from a specified height with a known initial speed. This is a classic projectile motion question, often covered in high school physics courses. Since the only force acting on the projectile in the vertical direction is gravity (and friction is neglected), we can use the following kinematic equation for free-fall:

h = ½gt²

Where:

h is the height the cannon ball falls, which is 4.9 meters,

g is the acceleration due to gravity, which is 9.8 m/s²,

t is the time in seconds.

Solving for t, we get:

t = √(2h/g)

t = √(2 × 4.9 m / 9.8 m/s²)

t = √(1)

t = 1 second

Therefore, the time it will take for the cannon ball to hit the ground is 1 second.

User Mwm
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