The temperature of a body falls from \(50^{\circ}\mathrm{C}\) to \(40^{\circ}\mathrm{C}\) in 10 minutes. If the temperature of the surroundings is \(20^{\circ}\mathrm{C}\)hen the temperature of the body after another 10 minutes will be:
1. \(36.6^{\circ}\mathrm{C}\)
2. \(33.3^{\circ}\mathrm{C}\)
3. \(35^{\circ}\mathrm{C}\)
4. \(30^{\circ}\mathrm{C}\)
A block of metal is heated to a temperature much higher than the room temperature and allowed to cool in a room free from air currents. Which of the following curves correctly represents the rate of cooling?
1. | 2. | ||
3. | 4. |
A certain quantity of water cools from \(70^{\circ}\mathrm{C}\) to \(60^{\circ}\mathrm{C}\) in the first 5 minutes and to \(54^{\circ}\mathrm{C}\) in the next 5 minutes.
The temperature of the surroundings will be:
1. | \(45^{\circ}\mathrm{C}\) | 2. | \(20^{\circ}\mathrm{C}\) |
3. | \(42^{\circ}\mathrm{C}\) | 4. | \(10^{\circ}\mathrm{C}\) |
Hot coffee in a mug cools from \(90^{\circ}\mathrm{C}\) to \(70^{\circ}\mathrm{C}\) in 4.8 minutes. The room temperature is \(20^{\circ}\mathrm{C}\). Applying Newton's law of cooling, the time needed to cool it further by \(10^{\circ}\mathrm{C}\) should be nearly:
1. | 4.2 minute | 2. | 3.8 minute |
3. | 3.2 minute | 4. | 2.4 minute |