Statement about ball thrown upwards

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A ball thrown vertically upwards experiences air resistance, affecting its motion. The incorrect statement is A, as acceleration is not zero at maximum height due to gravity still acting on the ball. The time taken for the ball to ascend is shorter than the descent time because of air resistance, making B correct. Statement C is accurate since the distance traveled upwards and downwards remains the same despite air resistance. Statement D is also correct, indicating that the net downward acceleration during upward motion exceeds 9.81 m/s² due to the combined effect of gravitational and resistive forces.
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Homework Statement


A ball is thrown vertically upwards and air resistance is NOT negligible.Which of the folloiwng statement is incorrect.
A:At maximum height,acceleration is zero.
B: Time taken for ball to travel upwards is shorter than time taken to travel down
C: Distance traveled for upward and downward motion are the same.
D: Magnitude of acceleration for the upward motion is always greater than 9.81ms-2


Homework Equations





The Attempt at a Solution


I choose A instantly as i knew there is acceleration downwards due to gravity.I was right though.
But i have no clue why D is correct?If a ball is facing air resistance wouldn't it slow down(Net force is pointing towards Earth)?
 
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so when the ball is going upwards, what are the forces acting on it
 
SHISHKABOB said:
so when the ball is going upwards, what are the forces acting on it
Downward:
Resistive force due to air resistance
Gravitational force due to gravity
Upward:
Zero?
 
right, so if there's two forces in the downwards direction, and one of them is gravity, then what can we say about the total force acting on the ball
 
SHISHKABOB said:
right, so if there's two forces in the downwards direction, and one of them is gravity, then what can we say about the total force acting on the ball

Yes,but won"t it be that total downward force is larger than 9.81ms-2?
But Option D seems to imply that it is accelerating upward.
 
chewchun said:
Yes,but won"t it be that total downward force is larger than 9.81ms-2?
But Option D seems to imply that it is accelerating upward.

no it's just asking about the acceleration *during* the upward motion
 
SHISHKABOB said:
no it's just asking about the acceleration *during* the upward motion

So option D is saying,When it is traveling upwards,net force/acceleration is acting downwards but it's magnitude is larger than 9.81 due to presence of air resistance?
 
that's what D appears to be saying, is that what you think is happening?
 
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