A ball is thrown vertically upwards. At its highest point, the ball's
Answer and explanation
Correct answer: C. velocity is zero and its acceleration is 9,8 m·s⁻² downwards
- Step 1: At the top the velocity changes sign, so it is zero for an instant; the only force is weight, giving g downwards.
Answer
velocity is zero and its acceleration is 9,8 m·s⁻² downwards.
Why not the others: velocity is zero and its acceleration is zero: gravity still acts, so the acceleration is not zero. velocity is 9,8 m·s⁻¹ upwards and its acceleration is zero: the ball has stopped momentarily, so the velocity is not 9,8 m·s⁻¹. velocity is zero and its acceleration is 9,8 m·s⁻² upwards: the acceleration due to gravity is always downwards.
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