Name the material used for making a Calorimeter. Why is a Calorimeter made up of thin sheets of the this material?

The Calorimeter box is made up of Copper. A calorimeter is a device used to measure the quantity of heat transferred to or from an object. Cu is highly malleable, and hence very thin box of small mass can be made. Copper is a good conductor of heat. Calorimetry is the process of measuring the amount of heat released or absorbed during a chemical reaction. A calorimeter box is made up of Copper because (i) Cu has low specific heat capacity, and thus it reaches the equilibrium temperature quickly by absorbing a small amount of heat. (ii) Cu is highly malleable and hence a very thin box of small mass can be made thus decreasing the heat capacity of the box. This makes sure the calorimeter absorbs or liberates a small amount of heat during the heat exchange.

Calorimetry is the study that related with determining the changes in energy of a system by measuring the heat exchanged with the surroundings and by this holding the law of conservation of energy.

The diagram above shows a circuit with the key k open. Calculate the resistance of the circuit when the key k is closed. Calculate the current drawn from the cell when the key k is closed.

Data given, voltage V = 3 . 3 V , When the key k is closed resistance 2 Ω and 3 Ω are in series. If equivalent resistance is R 1 then R 1 = 2 Ω + 3 Ω = 5 Ω This R 1 and 5 Ω are in parallel so if equivalent resistance is R 2 then: R 2 = R 1 × 5 R 1 + 5 = 5 × 5 5 + 5 = 25 10 = 2 . 5 Ω R 2 and internal resistance of the battery ( 0 . 5 Ω ) are connected and they are in series. If equivalent resistance is R T , so R T = 2 . 5 Ω + 0 . 5 Ω = 3 Ω Hence, the Resistance of the circuit when key K is closed is 3 Ω By ohm's law I = V R = V R T = 3 . 3 V 3 Ω = 1 . 1 A Thus, the current drawn from the cell when key K is closed is 1 . 1 A .