Two or more progressive waves can travel simultaneously in a medium without affecting the motion of one another. When they reach at a point, the resultant displacement of the particle at that point is equal to the vector sum of the displacements produced by each wave separately. This is obtained accRead more

Given, Velocity of wave= 100 m/s Wavelength= 20cm = 0.2m Frequency= ? Angular frequency=? Now, Velocity of wave= frequency * wave length or, 100 = frequency * 0.2 or, 100/0.2 = frequency so, frequency = 500 Hz We know, time period(T) = 1/f = 1/500 = 0.002 s Again, Angular frequency = (2*pi)/T = (2*pRead more

Let, the required number be x. According to the question, 75% of x - 75=75 or, (75/100) *x = 75+75 or, 0.75*x = 150 or, x =150/0.75 so, x = 200 Therefore, required number is 200.

In parallel grouping, Current(I)= nE/(nR+r) If nR>>r, then 'r' can be neglected, I= nE/nR or,I = E/R [i.e. current due to one cell] So,if the cells have very small internal resistance or in case the cells are new, the parallel grouping gives current equal to given by single cell.

## Wave motion

## Prasiddhi Dhungana

Two or more progressive waves can travel simultaneously in a medium without affecting the motion of one another. When they reach at a point, the resultant displacement of the particle at that point is equal to the vector sum of the displacements produced by each wave separately. This is obtained accRead more

## Wave

## Prasiddhi Dhungana

Given, Velocity of wave= 100 m/s Wavelength= 20cm = 0.2m Frequency= ? Angular frequency=? Now, Velocity of wave= frequency * wave length or, 100 = frequency * 0.2 or, 100/0.2 = frequency so, frequency = 500 Hz We know, time period(T) = 1/f = 1/500 = 0.002 s Again, Angular frequency = (2*pi)/T = (2*pRead more

## IQ

## Prasiddhi Dhungana

"Teapot"

## I.Q

## Prasiddhi Dhungana

Let, the required number be x. According to the question, 75% of x - 75=75 or, (75/100) *x = 75+75 or, 0.75*x = 150 or, x =150/0.75 so, x = 200 Therefore, required number is 200.

## Electromotive force (Current electricity)

## Prasiddhi Dhungana

In parallel grouping, Current(I)= nE/(nR+r) If nR>>r, then 'r' can be neglected, I= nE/nR or,I = E/R [i.e. current due to one cell] So,if the cells have very small internal resistance or in case the cells are new, the parallel grouping gives current equal to given by single cell.