72) A coil with a self-inductance of 6.0 H is connected to a dc battery through a switch. As soon as the switch is closed, the rate of change of current is 2.0 A/s. What is the emf induced in this coil at this instant

12.0 V

Explanation:

The E.M.F induced in a coil is given as,

E = LΔ(i/t) Equation 1

Where E = E.M.F induced in the coil, L = inductance of the coil, Δ(i/t) = rate of change of current when the switch is closed

Given: L = 6.0 H, Δ(i/t) = 2.0 A/s.

Substitute into equation 1

E = 6.0(2.0)

E = 12.0 V.

Hence the emf induced in the coil = 12.0 V

wind moving at higher speeds will transfer more energy to the water, resulting in stronger waves.

force is based upon mass and acceleration.the statement is not always true.

it can be explained from newton's second law of motion.

as per newton's second law of motion the rate of change of momentum is directly proportional to the applied force and takes place along the direction of force.

mathematically it can be written as -

                                              ⇒      

here   k is the proportionality constant whose value is 1.

                                                            [a is the acceleration=dv/dt]

hence we see that force not only depends on mass and acceleration but also on velocity and rate of change of mass. force f will depend on mass and acceleration only when mass is constant.

hence the statement that force is based upon mass and acceleration is false.