Answer:

Explanation:
Firstly finding 
So,

Substitute 

Exchange the values of x and y

Solving for y

Adding 5 to both sides

Dividing both sides by 10

Replace 

For x = -4


The wheel and axle increases your force. You exert your input force over a long distance and the output force is increased over a shorter distance. (Because the wheel is larger than the axle, the axle rotates and exerts a large output force.) A simple machine with a grooved wheel with a rope or cable wrapped around it.
Answer:

Explanation:
When wings of the airplane makes an angle of 40 degree with the horizontal so here we can say that force due to air is having two components


now we know that


also we know that


now plug in all data in above equations




Answer:
Moving them farther apart
Explanation:
The electric field between the two charges Q and q separated by a distance r is given by

It shows that the electric field is inversely proportional to the square of the distance between two charges.
So, as the distance between two charges increases, the electric filed between the two charges decreases.
The work done by the battery is equal to the charge transferred during the process times the potential difference between the two terminals of the battery:

where q is the charge and

is the potential difference.
In our problem, the work done is W=39 J while the potential difference of the battery is

, so we can find the charge transferred by the battery: