since child is moving along with the wagon and we need to find the acceleration of child inside that wagon then in this case the system of interest must be child + wagon
System of interest will be the system that is used to find the force or acceleration using Newton's law
Here we have to assume that system on which if we will calculate the forces then the net value of force on that system will help to calculate the unknown quantities
So here our system will be boy + wagon
Answer:
<em>The force is now 9 times the original force</em>
Explanation:
<u>Coulomb's Law
</u>
The electrostatic force between two charged particles is directly proportional to the product of their charges and inversely proportional to the square of the distance between them.
Coulomb's formula is:
Where:
q1, q2 = the particles' charge
d= The distance between the particles
Suppose the distance is reduced to d'=d/3, the new force F' is:
The force is now 9 times the original force
The wave speed completely depends on the characteristics and properties of the medium . . . physical properties for mechanical waves, electrical properties for electromagnedtic waves.
So if you want to change the speed of a wave, you have to change the medium . . . shoot it through some different kind of stuff. <em>(B) </em>
Answer:
By holding another magnet close to it. If the object is attracted to the magnet, then it too is magnetic.
You do this one just like the other one that I just solved for you.
For this one ...
The density of the object is 2.5 gm/cm³.
We know that every cm³ of it we have contains 2.5 gm of mass.
We have to find out how many cm³ we have.
The question tells us: We have 2.0 cm³.
Each cm³ of space that the object occupies contains 2.5 gm of mass.
So the 2.0 cm³ that we have contains (2 x 2.5 gm) = 5 gms.
That's the mass of our object.
