Reflection of Light — Science STD 10 — Question

Which is the better way to connect lights and other electrical appliances in domestic wiring: series circuits or parallel circuits? Why?

Name the type of mirrors used in the design of solar furnaces. Explain how high temperature is achieved by this device.

Name the two types of spherical mirrors. What type of mirror is represented by the:

1. Back side of a shining steel spoon?
2. Front side of a shining steel spoon?

At what distance from a converging lens of focal length 12cm must an object be placed in order that an image of magnification 1 will be produced?

Define the term power of accommodation. Write the modification in the curvature of the eye lens which enables us to see the nearby objects clearly?

Should the resistance of an ammeter be low or high? Give reason.

Draw ray diagrams showing the image formation by a convex lens when an object is placed:

Between focus and twice the focal length of the lens.

Name the part of the eye where the image is formed by the eye lens. What is the nature of the image formed? How is this image sent to the brain?

State two hazards associated with the use of electricity.

A student focuses the image of a well illuminated distant object on a screen using a convex lens. After that he gradually moves the object towards the lens and each time focuses its image on the screen by adjusting the lens.

1. In which direction-towards the screen or away from the screen, does he move the lens?
2. What happens to the size of the image-does it decrease or increase?
3. What happens to the image on the screen when he moves the object very close to the lens?