Physics
(i) Name the radiations which are absorbed by greenhouse gases in the earth’s atmosphere.
(ii) A radiation X is focused by a particular device on the bulb of a thermometer and mercury in the thermometer shows a rapid increase. Name the radiation X.
(iii) Name two factors on which the heat energy liberated by a body depends.
Related Questions
(i) How is the transference of heat energy by radiation prevented in a calorimeter?
(ii) You have a choice of three metals A, B and C, of specific heat capacities 900 Jkg-1°C-1, 380 Jkg-1°C-1 and 460 Jkg-1°C-1 respectively, to make a calorimeter. Which material will you select? Justify your answer.
Calculate the mass of ice needed to cool 150 g of water contained in a calorimeter of mass 50 g at 32°C such that the final temperature is 5°C.
Specific heat capacity of calorimeter = 0.4 J g-1 °C-1
Specific heat capacity of water = 4.2 Jg-1°C-1
Latent heat capacity of ice = 330 Jg-1
A lens forms an upright and diminished image of an object when the object is placed at the focal point of the given lens.
(i) Name the lens.
(ii) Draw a ray diagram to show the image formation.
A ray of light travels from water to air as shown in the diagram given below:
(i) Copy the diagram and complete the path of the ray. Given the critical angle for water is 48°.
(ii) State the condition so that total internal reflection occurs in the above diagram.