Question

1. Write the effects of force in the following situation: (a) A batsman hits a cricket ball for a six (b) A goalkeeper saves a goal by grasping the ball (c) Pressing the inflated balloon gently between palms
2. Write the three properties of air in minimising friction in the smooth ride of a hovercraft.
3. (a) Differentiate between lignite and anthracite on the basis of their carbon content and moisture.
(b) Name the petroleum products (i) used for making roads (ii) used as a fuel in boilers.
4. (a) What happens when magnesium ribbon is dipped in copper sulphate solution? Write the two changes that could be observed.
(b) Name the chemical reaction that had taken place in “(a)”. Define the chemical reaction.
(c) Write the chemical equation for the above reaction (a).
5. (a) Riya wanted her silver ring to look like gold. Explain with the help of a neatly drawn electrolytic cell, how the silver ring can be made to look like gold. (b) Name the anode and cathode used in a voltaic cell.
6. (a) (a) You are given a convex lens of focal length 15 cm. Draw a ray diagram to show the nature, size and position of the image formed when an object is kept at a distance of 40 cm.
(b) A student performs an experiment in the lab to study image formation by using different types of lenses. When a pen is seen through lenses A and B one by one, it appears as shown in the figure given below. Mention the name/type of lens A and B, respectively.
(c) Write the significance of the incident ray which passes through the optical centre of a lens.

Answer 1

Answer:

1 when a batsman hits a cricket ball for a six the direction as well as speed of the ball changes b. force can stop the motion or force c.