(English Medium) ICSE Class 10 - CISCE Question Bank Solutions

You have three resistors of values 2Ω, 3Ω and 5Ω. How will you join them so that the total resistance is more than 7Ω?

1) Draw a diagram for the arrangement

2) Calculate the equivalent resistance.

State whether the resistivity of a wire changes with the change in the thickness of the wire.

 Define the unit of resistance (or Define the unit "ohm").

Write S.I. unit of moment of couple.

What do you understand by the term couple?

Prove that

Moment of couple = Force × couple arm.

What do you understand by an ideal machine? 

How does ideal machine differ from a practical machine ?

How is mechanical advantage related to the velocity ratio for an ideal machine?

State one reason why is mechanical advantage less than the velocity ratio for an actual machine.

Shows a uniform metre scale of weight W supported on a fulcrum at the 60 cm mark by applying the effort E at the 90 cm mark.

1. State with reason whether the weight W of the scale is greater than, less than or equal to the effort E.
2. Find the mechanical advantage in an ideal case.

Define the term dispersion of light.

Explain the cause of dispersion of white light through a prism.

Explain briefly, with the help of a neat labelled diagram, how white light gets dispersed by a prism. On which surface of a prism, there is both dispersion and deviation of light, and on which surface of the prism, there is only deviation of light ?

The diagram below shows the path taken by a narrow beam of yellow monochromatic light passing through an equiangular glass prism. If the yellow light is replaced by a narrow beam of white light incident at the same angle, draw another diagram to show the passage of white light through the prism and label it to show the effect of prism on the white light.

1. A beam of monochromatic light undergoes minimum deviation through an equiangular prism, how does the beam pass through the prism, with respect to its base?
2. If white light is used in the same way as in part (a) above, what change do you expect in the emergent beam?
3. What conclusion do you draw about the nature of white light in part (b)?

What conclusion do you draw about the nature of white light in part (b)?

What do you understand by the term spectrum?

A ray of white light is passed through a glass prism and a spectrum is obtained on a screen.

1. Name the seven colours of the spectrum in order.
2. Do the colours have the same width in the spectrum?
3. Which of the colour of the spectrum of white light deviates (i) the most, (ii) the least?

Complete the ray diagram given below to show the nature of light produced on the screen.