65. A length of wire is bent into a closed loop and a magnet is plunged into it, inducing a voltage and, consequently, a current in the wire. A second length of wire, twice as long, is bent into two loops of wire, and a magnet is similarly plunged into it. Twice the voltage is induced, but the current is the same as that produced in the single loop. Why

The resistance of the second wire is two times that of the first wire. Even though the voltage doubles, current still remain the same.

Explanation:

The voltage induced is directly proportional to the number of loops of the wire. Resistance is directly proportional to the length of the wire as long as all other parametersare constant in the formula R=PL/A. The second wire has twice the length and twice the number of turns than the first wire.

weight of the box is given as

here this is placed on the inclined of angle 42 degree

now this weight will have two components one is along the incline other is perpendicular to it

so here we need to apply a force parallel to incline opposite to its component of weight

so here the component of weight is given as

here we have

so it requires 75 n force to move it upwards