Question

A rock is thrown vertically upward from the surface of the earth. The rock rises to some maximum height and falls back toward the surface of the earth. Which one of the following statements concerning this situation is true if air resistance is neglected?

Answer 1

(a) As the ball rises, its acceleration vector points upward.
(b) The ball is a freely falling body for the duration of its flight.
(c) The acceleration of the ball is zero when the ball is at its highest point.
(d) The speed of the ball is negative while the ball falls back toward the earth.
(e) The velocity and acceleration of the ball always point in the same direction.

Answer 2

It isn't C >.> I mistook velocity with acceleration

Answer 3

Well, think of the gravitational constant with application of air resistance.

Answer 4

I feel like this is one of those questions where they're all kind of right but which is the most correct answer

Answer 5

OH if Air resistance is neglected

Answer 6

Our physics problems always neglect air resistance, we aren't advanced enough to account for it

Answer 7

Technically it would be E.

Answer 8

Or B. Both are rational.

Answer 9

Yeah that's what I was thinking too, but I only vaguely recalled the drawings we did in class and wasn't completely sure

Answer 10

B is a little too general though.

Answer 11

Agreed, I don't think it accounts for the time going up into the air, just down

Answer 12

You apply positional force when throwing the ball upwards, however the acceleration and velocity is still drawing towards the gravitational pull of the Earth.

Answer 13

But then it can't be E right? The acceleration will always pull down due to gravity, and it has a positive velocity when it's thrown into the air

Answer 14

No it doesn't xD. There is no positive and negative connotation. Velocity is a vector. It cannot be negative. Negative is only used to show direction.

Answer 15

Is this Kinematics?

Answer 16

Ah, yeah, you're right. Thanks. The rest of the answer choices don't make sense anyways

Answer 17

More like basic Classical mechanics Jess lol

Answer 18

Well, they do that to make you think about it.

Answer 19

Yeah, I chose C initially because I was working on 3 hours of sleep and confused acceleration with velocity LOL. Thanks, happy

Answer 20

It's gonna cost you something though ;) **Turns on Barry White**

Answer 21

Lol, can I pay with my thanks?

Answer 22

Oh you def. can... **points downwards** LOL

Answer 23

In your dreams lol

Answer 24

I would say A because acceleration is always downward while an object is in free fall.

Answer 25

Yeah I thought about that but that doesn't account for the toss up, just the journey down

Answer 26

Hmm, well good luck.

Answer 27

Thanks