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A 5.0 kg cannonball is dropped from the top of a tower. It falls for 1.6 seconds before slamming into a sand pile at the base of the castle. What is the velocity of the cannonball just before it hits the ground ?

User Jolanta
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1 Answer

7 votes

Answer:

15.7 m/s

Step-by-step explanation:

The motion of the cannonball is a accelerated motion with constant acceleration g = 9.8 m/s^2 towards the ground (gravitational acceleration). Therefore, the velocity of the ball at time t is given by:


v(t)=u + gt

where

u = 0 is the initial velocity

g = 9.8 m/s^2 is the acceleration

t is the time

If we substitute t=1.6 s into the equation, we find the final velocity of the cannonball:


v(1.6 s)=0+(9.8 m/s^2)(1.6 s)=15.7 m/s

User Fstamour
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