Help with physics: velocity/acceleration question?

Question

An object is thrown vertically into the air at speed V, upwards. What is the sign (+,-,0) of its acceleration and the sign of its velocity?

Answer 1

The convention usually is that the acceleration will be -ve (action of gravity) and the initial velocity will be positive.

Answer 2

If the boy drops the ball to loose fall, right here ought to notice preliminary velocity is 0 m/s very final velocity is 14.7 m/s Acceleration is (gravity =9.8 m/s2) distance = a million/2 * gt^2 = a million/2 * 9.8 * 4 = 19.6 m If the boy skill throws the ball with preliminary velocity of 14.7 m/s, then right here ought to notice d = Vi *t + a million/2 gt^2 d= 14.7*2 + a million/2*9.8*4 = 40 9 m

Answer 3

its acceleration is negative, due to the force of gravity being opposite to the direction of its velocity. its velocity's sign is positive because it is moving away from the origin, where it left the person's hand.

Answer 4

When you throw it up it will eventually slow down
-V, reach V 0, and fall down +V.
The reason is on earth all objects are subject to the earth's gravitational force, making objects "deccelerates" > a= -9.98m/s when they go up, it is a minus because gravity pulls on the object that is going up.
It also pulls it down, then the acceleration is positive, >a=+9,98 m/s. It is obvious that it is a positive acceleration because the object is going down.
It has to reach V=0 before it changes its directions from upward to downwards.

Always think of the gravitional force pulling the object down, wether its going up or not.
- when its going up
+ when its falling down

Answer 5

The initial velocity will , of course, be positive but it will slow very quickly. Simple huh?
Jonnie

Answer 6

its velocity should be + and its acceleration should be -