a cricket ball is hit so that it travels straight up in the air and it require 3 second to reach the maximum height its initial

The forces are called balanced force because the force acting apon the object are equal and the opposite object is said to be in the state of equilibrium. (Please correct me if I'm wrong)

• The only force acting on the ball, and thus the net force, is due to its own weight, with magnitude

<em>w</em> = <em>m</em> <em>g</em> = (0.4 kg) (9.8 m/s²) ≈ 3.9 N

pointing downward.

• The ball is in free fall, so its acceleration is <em>g</em> = 9.8 m/s² (also pointing downward).

• The ball is dropped from a height of 49 m, so its height <em>y</em> at time <em>t</em> is

<em>y</em> = 49 m - 1/2 <em>g</em> <em>t</em> ²

Set <em>y</em> = 0 and solve for <em>t</em> :

0 = 49 m - 1/2 <em>g t</em> ²

<em>t</em> ² = (98 m) / <em>g</em>

<em>t</em> = √((98 m) / <em>g</em>) = √(10) s ≈ 3.2 s

• The ball's velocity <em>v</em> at time <em>t</em> is

<em>v</em> = - <em>g t</em>

so that at the time found previously, the ball will have attained a velocity of

<em>v</em> = - <em>g</em> (3.2 s) ≈ -31 m/s

and thus a <em>speed</em> of about 31 m/s.

An ion is a charges particle that has either more or fewer electrons than protons

Where are the answers

An example of a balanced force is two cards leaning against each other and not falling over, or two football players blocking each other but neither overpowering the other. An example of an unbalanced force is two cards leaning on each other then falling over, or two football players blocking each other, then one tackles the other.