Answer:
The box of rocks will have depression which can be seen without touching the box.
Explanation:
The density of rocks is very large as compared with napkins. So, the weight of the rocks will be much more greater than that of napkins.
As both boxes have same volume the heavier box will show depression on the lower surface as compared to the lighter box. So, the box of rocks will have depression which can be seen without touching the box.
I don’t really know the answer cause I need more information about the question
Answer:


Explanation:
v = Velocity of the elevator = 3.1 m/s
= Angle of the slope = 
Vertical component is given by

The vertical component of the velocity is
.
Horizontal component is given by

The horizontal component of the velocity is
.
Answer:
The charge density in the system is 
Explanation:
To solve this problem it is necessary to keep in mind the concepts related to current and voltage through the density of electrons in a given area, considering their respective charge.
Our data given correspond to:

We need to asume here the number of free electrons in a copper conductor, at which is generally of 
The equation to find the current is

Where
I =Current
V=Velocity
A = Cross-Section Area
e= Charge for a electron
n= Number of free electrons
Then replacing,


Now to find the linear charge density, we know that

Where:
I: current intensity
Q: total electric charges
t: time in which electrical charges circulate through the conductor
And also that the velocity is given in proportion with length and time,

The charge density is defined as

Replacing our values


Therefore the charge density in the system is 
Complete Question
A 75 kg man and a 100. Kg woman are playing tug of war on a frictionless surface. The man accelerates toward the woman at 2.0 m/s2.How much force does she use to pull on the rope
Answer:
The value is 
Explanation:
From the question we are told that
The mass of the man is 
The mass of the woman is
The acceleration of the man is 
Generally the force which she used to pull the rope is mathematically represented as

=> 
=> 