Answer:
hi here is your answer and this is a very important question.
Explanation:
A lever is a rigid bar with three parts: the fixed point around which the bar pivots is the fulcrum: the effort arm (in-lever arm) is the part of the lever to which force is applied; the resistance arm (out-lever arm) is the part that bears the load to be moved.
Answer:
<h2>A. a spring & B. a well dried into an aquifer.</h2>
Here when an object is placed on the level floor then in that case there are two forces on the object
1). Weight of object downwards (mg)
2). Normal force due to floor which will counterbalance the weight (N)
so when no force is applied on the box at that time normal force is counter balanced by weight.
Now here it is given that A person tried to lift the box upwards
So now there are two forces on the box
1). Applied force of person
2). Normal force due to ground
So now these two forces will counter balance the weight of the crate
So we can write an equation for force balance like

given that

here
m = 30 kg and
g = acceleration due to gravity = 10 m/s^2

now from above equation


So force applied by the person must be 150 N
So that we do not contaminate it with microorganisms or garbage or other human stuff.
-- Take a straight ruler.
-- Lay it down with the 'zero' mark at the start point.
-- Rotate it around the start point until the end point is also touching the edge of the ruler.
-- From the marks on the ruler, read the straight-line distance from the start point to the end point.
-- Without moving the ruler, observe and write down the DIRECTION from the start point to the end point.
-- The Displacement is the straight-line distance and direction from the start point to the end point.