Question

A rock is thrown vertically upward from the origin of a reference frame. The rock reaches the peak of its trajectory and then it returns back to the origin where it comes to rest. Using the upward direction as positive, select True or False for the following statements. False The acceleration of the rock is negative throughout the whole motion. True The position of the rock is positive or zero throughout the whole motion. False The velocity of the rock is positive throughout the whole motion. False The acceleration of the rock is zero at the peak of the trajectory

Answer 1

Answer:

The acceleration of the rock is negative throughout the whole motion. (TRUE)

The acceleration of the rock is zero at the peak of the trajectory (FALSE)

The velocity of the rock is positive throughout the whole motion (FALSE)

The position of the rock is positive or zero throughout the whole motion (TRUE)

The velocity of the rock is positive throughout the whole motion (FALSE)

Explanation:

1)The acceleration of the rock is negative throughout the whole motion. (TRUE)

Using the upward direction as positive

Then, The acceleration of the rock is negative throughout the whole motion.

2)The acceleration of the rock is zero at the peak of the trajectory.(FALSE)

Only the velocity can be zero at the peak the trajectory, the acceleration is not zero

3)The velocity of the rock is positive throughout the whole motion (FALSE)

Using the upward direction as positive, The velocity of the rock is only positive when going in upward direction and vice versa

4)The position of the rock is positive or zero throughout the whole motion (TRUE)

When the rock get down it will have a zero position, then when it get to the peak it will have positive position