Why resistance is there in the auxiliary circuit of potentiometer? what is it's purpose?​

Suppose an objects initial velocity is 10m/s and it’s final velocity is 4 m/s. mass is constant. what can best be concluded about the object based in the work-energy theorem

What will a positive and a negative charge do if they are separated from each other?

An open cart is moving along a straight frictionless horizontal track. when rain starts falling vertically into the cart, what happens to the speed of the cart?