A stone is thrown downward from a cliff. Take "up" to be the positive direction. Which of the following statements is true about the stone?Select one:a.The velocity is positive, the acceleration is positive, and the speed is positive.b.The velocity is positive, the acceleration is negative, and the speed is positive.c.The velocity is negative, the acceleration is negative, and the speed is positive.d.The velocity is negative, the acceleration is negative, and the speed is negative.

3. What is the difference between positive and negative acceleration?

A ball is thrown straight up. Which of the following statements about its velocity and acceleration is true during its flight (ignoring air resistance)?i. The velocity is always in the same direction as the acceleration.ii. The acceleration is always directed upward.iii. The acceleration is always directed downward.iv. The velocity is zero at the highest point.Select one:a.(i) and (iii) onlyb.(iii) and (iv) onlyc.(iv) onlyd.(ii) and (iv) onlye.(i), (iii) and (iv) only

Which of the following statements are true regarding displacement, velocity, and acceleration for an object in 1-D motion?  (Choose all that apply)  Group of answer choicesIf an object is speeding up, then its acceleration has the same sign (positive or negative) as its velocity.If an object is speeding up, then the sign (positive or negative) of its acceleration is opposite to the sign of its velocity.If an object is slowing down, then the sign (positive or negative) of its acceleration is opposite to the sign of its velocity.If an object is slowing down, then its acceleration has the same sign (positive or negative) as its velocity.If an object is speeding up, then its displacement has the same sign (positive or negative) as its velocity.If an object is speeding up, then the sign (positive or negative) of its displacement is opposite to the sign of its velocity.If an object is slowing down, then its displacement has the same sign (positive or negative) as its average velocity.If an object is slowing down, then the sign (positive or negative) of its displacement is opposite to the sign of its average velocity.

Which of the following statements is true for the acceleration of the projectile (of the previous question)?Group of answer choicesIt is zero in horizontal and g downward in vertical directionIt is g downward in both horizontal and vertical directionsIt is g downward in horizontal direction and zero in vertical directionIt is zero in horizontal and g upward in vertical directionIt is zero in both horizontal and vertical directions

An object is shot vertically upward. While it is rising: Group of answer choicesits velocity and acceleration are both decreasingits velocity and acceleration are both upwardits velocity is downward and its acceleration is upwardits velocity and acceleration are both downwardits velocity is upward and its acceleration is downward