Answer:
Work done in both the cases will be same
Explanation:
As we know that the work done against gravity is given as

here we know that gravitational force is a conservative force and the work done against gravitational force is independent of the path
So here the work done by person to move the object between two different heights will be independent of the path they choose
So for the first person and second person will be same in both the cases because the height through which the boxes are transferred will be same in both the cases
Answer:
The value is 
Explanation:
From the question we are told that
The magnitude of the horizontal force is 
The mass of the crate is 
The acceleration of the crate is 
Generally the net force acting on the crate is mathematically represented as

Here
is force of kinetic friction (in N) acting on the crate
So

=> 
To solve this problem we will apply the concepts related to the Electrostatic Force given by Coulomb's law. This force can be mathematically described as

Here
k = Coulomb's Constant
Charge of each object
d = Distance
Our values are given as,


d = 1 m
a) The electric force on charge
is


Force is positive i.e. repulsive
b) As the force exerted on
will be equal to that act on
,


Force is positive i.e. repulsive
c) If
, a negative sign will be introduced into the expression above i.e.


Force is negative i.e. attractive
The dance that was being created was Hip Hop dance!
Strange as it may seem, the object would keep moving, in a straight line and at the same speed, until it came near another object. Its momentum and kinetic energy would never change. It might continue like that for a billion years or more.
Have a look at Newton's first law of motion.