Answer:
Explanation:
Given
mass of children 

distance between two children 
suppose small child is at a distance of x m from pivot point
so torque of small child and heavier child must be equal



Answer: 3.41 s
Explanation:
Assuming the question is to find the time
the ball is in air, we can use the following equation:

Where:
is the final height of the ball
is the initial height of the ball
is the initial velocity of the ball
is the time the ball is in air
is the acceleration due to gravity

Then:


Multiplying both sides of the equation by -1 and rearranging:

At this point we have a quadratic equation of the form
, which can be solved with the following formula:
Where:
Substituting the known values:
Solving the equation and choosing the positive result we have:
This is the time the ball is in air
Answer:
New force, 
Explanation:
It is given that,
Force acting between two charged particles, 
We need to find the force if they are moved so they are only one-eighth as far apart.
The force between two charged particles separated at a distance of r is given by :
............(1)
If the charges are one-eighth as far apart then, r' =(1/8)r and new force is given by :
..........(2)
Dividing equation (1) and (2) :


F' = 48000 N
or

Hence, this is the required solution.
Making a wire thicker has the same effect as making a road wider. It makes it easier for the electron traffic to flow. The resistance decreases, and the current (traffic) increases.