Answer:
<u>CHEMICAL CHANGE</u>:
A change in which one or more substances are converted into new substances is a <em>chemical change</em>.
<u>EXPLANATION:</u>
Chemical changes occur when a substance combines with another to form a new substance, called chemical synthesis or, alternatively, chemical decomposition into two or more different substances.
<u>EXAMPLE:</u>
<em>Examples of Chemical Change in Everyday Life
</em>
Burning of paper and log of wood.
Digestion of food.
Boiling an egg.
Chemical battery usage.
Electroplating a metal.
Baking a cake.
Milk going sour.
Various metabolic reactions that take place in the cells.
Answer:
16.935 N
Explanation:
In order to make the box start moving, the level force applied on the box (F) must be greater than the force of static friction that keeps the box at rest, which is equal to

where
is the coefficient of static friction
(mg) = 30 N is the weight of the box
Therefore, the condition for F must be:

So, the applied force must be greater than this value.
If you are given distance and a period of time, you can calculate
the speed. The velocity of an object is the rate of change of its position with
respect to a frame of reference, and is a function of time. Velocity is
equivalent to a specification of its speed and direction of motion (e.g. 60
km/h to the north).
Answer:
Ans= 9
See attached picture for clearer solution.
Explanation:
The net electrostatic force acting on charge A = 2/ 2 + 2 /(2) 2 − 2 /(3) 2 = 2 / 2 (1 + 1/4 – 1/9 ) = 41/36 2/2 .
The net electrostatic force acting on charge B = 2/2 + 2/(2)2 − 2/2 = 1/4 2/d2 .
The net electrostatic force acting on charge C = 2/2 + 2/(2)2 + 2/2 = 2/2 (1 + 1 4 + 1) = 9/4 2/2 .
The net electrostatic force acting on charge D = 2/2+ 2 /(2)2 + 2/(3)2 = 2 /2 (1 + 1/4 + 1/9 ) = 49/36 2/ 2 .
The ratio of the largest to the smallest net force = 9/4*2/2 / 1/4 2/2 . = 9