A car starts from rest and accelerates at 5 m/s². At t=4 s, a ball is dropped out of a window by a person sitting in the car. What is the velocity and acceleration of the ball at t=6 s? (Take g=10 m/s²)

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(4) 20√2 m/s, 10 m/s². Given: car from rest at 5 m/s²; ball released at t=4 s; state wanted at t=6 s, with g=10 m/s². Idea: at release the ball shares the car's horizontal velocity, and from then on it is a projectile with only gravity acting. Car's speed at release: v=0+5(4)=20 m/s, horizontal. That horizontal component is unchanged afterwards, so vₓ=20 m/s. Falling for 6-4=2 s: v_y=gt=10(2)=20 m/s downward. |v⃗|=√20²+20²=20√2 m/s. The only force on the ball is gravity, so its acceleration is 10 m/s² downward.

A car starts from rest and accelerates at 5 m/s². At t=4 s, a ball is dropped out of a window by a person sitting in the car. What is the velocity and acceleration of the ball at t=6 s? (Take g=10 m/s²)

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