1) What is the acceleration of a rock at the top of its trajectory when thrown straight upward?

Question

Explain whether or not the answer is zero by using the equation a = F/m as a guide to your thinking.


2)A rocket fired from its launching pad not only picks up speed, but its acceleration also increases significantly as firing continues. Why is this so? (Hint: About 90% of the mass of a newly launched rocket is fuel.)

Answer 1

1) The answer is not zero, it is -9.8 m/s(squrd). If A were 0 there would no force and since the rock changes speed, where is a force. The rock has it's own mass, which is constant. So this means that there has to be an acceleration of some sort the change the vectored velocity.

2) The rocket picks up speed, not because of it's booster, but because of it's mass. Acceleration = Force/Mass. Since we're losing fuel, we're losing mass. This in turn creates an increase of acceleration. :)

Answer 2

on the properly of the trajectory its % is 0. After it has reached the point, it comes down. How can the stone come down if it has no acceleration at this element. because the speed is 0, with techniques from Newton's first regulation of action it ought to stay in its state or relax for ever. Any merchandise dropped from a properly has an initial % 0. The acceleration by way of gravity pulls the article downward. a similar element occurs right here. It has reached a properly the position its % is 0. After that the earth pulls it downward with an acceleration . for this reason the acceleration of the rock is the acceleration by way of gravity. with the help of out its trajectory the acceleration interior the down route is a continuing and is an identical because the acceleration by way of gravity.

Answer 3

1) It depends where you were when you threw it. 'Straight up" implies that you are in some sort of gravity well so if you can't throw it very high then the acceleration due to gravity won't change that much - answer is not much less than it was just after you let go of it, normally.

2) read the hint - assume that F stays the same as the fuel is burnt.

Answer 4

the rock would be at zero because at that point gravity=acceliration and momentom, also the rocket gains speed and accelliration because one, the gravitational field is growing weeker,it is growing lighter do to loss of fuel and air resistance is becoming smaller

Answer 5

it is 0 because it does a form of a parabola. when at the top of its path, the object is no longer gaining accel. or losing accel. It also increases and decreases exponentially.