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

A pulley system has a velocity ratio 3. Draw a diagram showing the point of application and direction of load (L), effort (E) and tension (T). It lifts a load of 150 N by an effort of 60 N. Calculate its mechanical advantage. Is the pulley system ideal? Give reason.

State two advantages of an electromagnet over a permanent magnet.

Write the expressions for the equivalent resistance R of three resistors R₁, R₂ and R₃ joined in

1. parallel
2. series 

A light ray in passing from water to a medium

(a) speeds up

(b) slows down. In each case, give one example of the medium. 

How does the speed of light change when it passes from glass to water? 

A ray of light is passing from a transparent medium 1 to another transparent medium 2 (i) Speed up (ii) slows down. In each case, state whether the refractive index of medium 2 is equal to, less than or greater than the refractive index of medium 1. 

What do you understand by the statement the refractive index of glass is 1.5 for white light? 

The diagram alongside shows the refraction of a ray of light from air to a liquid.

1. Write the values of (i) angle of incidence, (ii) angle of refraction.
2. Use Snell’s law to find the refractive index of liquid with respect to air.

In fig 4.18, name the ray which represents the correct path of light while emerging out through a glass block. 

Fill in the blanks to complete the following sentence 

When light travels from a denser to a rarer medium, its speed ………………. 

Fill in the blanks to complete the following sentence 

The refractive index of glass with respect to air is 3/2. The refractive index of air with respect to glass will be ………………. 

How is the angle of emergence related to the angle of incidence when prism is in the position of minimum deviation? Illustrate your answer with help of a labelled diagram using an equilateral prism? 

Name the colour of white light which is deviated the most on passing through a prism. 

An object is viewed through a glass prism with its vertex pointing upwards. It appears to be displaced upward. Explain the reason. 

Fig 4.31 below shows a light ray of single colour incident normally on two prisms A and B. In each case draw the path of the ray of light as it enters and emerges out of the prism. Mark the angle wherever necessary. 

Complete Fig. 4.32 to show the path of the ray of single colour as it enters the prism and emerges out of it. Mark the angles wherever necessary. 

A Water pond appears to be 2.7 m deep. If the refractive index of water is 4/3, find the actual depth of the pond. 

A coin is places at the bottom of a beaker containing water (refractive index = 4/3) to a depth of 12 cm. By what height the coin appears to be raised when seen from vertically above? 

A postage stamp kept below a rectangular glass block of refractive index 1.5 when viewed from vertically above it, appears to be raised by 7.0 mm. Calculate the thickness of the glass slab.

What is meant by the statement the critical angle for diamond is 24°?