Mercury and Alcohol are two common liquids used in thermometers. The boiling point of mercury is , while its freezing point is . For alcohol, the boiling point is and the freezing point is . A thermometer is required in a laboratory to make measurements which are in the range . Which type of thermometer would be more suitable?
Important Questions on Heat
A device used for measuring the temperature of different objects is called a thermometer. The thermometer consists of a very fine glass tube which consists of a thin glass bulb at one end. The bulb is filled with thermometric liquid. After removing air, the other end of tube is sealed. The tube is protected by a thick glass tube called stem. On the stem the markings are given.
Which of these readings cannot be taken with the thermometer shown?
Two identical vessels are taken and painted white and black respectively. Then the same quantity of water is poured into each one of them. Both the vessels are left in the sun, and the temperature is noted regularly. The water temperature in the vessel painted white is recorded every five minutes as shown in the table below.
| Water temperature in white vessel | |
|---|---|
| After minutes | |
| After minutes | |
| After minutes | |
| After minutes | |
What is the temperature in the vessel likely to be minutes after it was left in the sun?
Rani has two bowls in front of her. Bowl P contains grams of ice, while bowl Q contains three kilograms of the same material. Both are heated and start melting. Which of the following will be true about the temperature at which the ice just starts melting, and the temperature at which the wax melts completely.
| Temperature at which ice starts melting | Temperature at which ice just melts completely | |
| A | Same for both | Lower for P |
| B | Lower for P | Lower for P |
| C | Same for both | Same for both |
| D | Lower for P | Same for both |
Lal conducts the following activity to check if colour has any effect on heat absorption.He takes four identical cans with the same amount of water but covered with different coloured papers and places them near a heat source as shown in the figure.
The temperature of the water in the cans is measured at regular intervals.
This experiment will not lead to correct result due to a mistake in the setup. The mistake is related to
The diagram below shows a block of wood stuck in a metal container.
Which of these is the best way to remove the block of wood undamaged?
