A circular plate, a cube and a sphere, all made up of same material and having the same mass, are heated to 300°C and left in a room. Which of them will have the slowest rate of cooling? A. Circular plate B. Cube C. Sphere D. All will cool at the same rate

The correct answer is: A. Circular plate.

The rate of cooling of an object depends on its surface area. The object with the largest surface area will cool the fastest. The circular plate has the largest surface area, followed by the cube, and then the sphere. Therefore, the circular plate will cool the fastest, followed by the cube, and then the sphere.

Here is a more detailed explanation:

The rate of cooling of an object depends on the following factors:

• The material of the object: The rate of cooling of an object depends on the specific heat of the material. The specific heat of a material is the amount of heat required to raise the temperature of 1 gram of the material by 1 degree Celsius. Materials with a high specific heat will cool more slowly than materials with
  Subscribe on YouTube
  a low specific heat.
• The mass of the object: The rate of cooling of an object depends on its mass. The larger the mass of the object, the more heat it will have stored, and the slower it will cool.
• The surface area of the object: The rate of cooling of an object depends on its surface area. The larger the surface area of the object, the more heat it will lose to the environment, and the faster it will cool.

In the case of the circular plate, cube, and sphere, all three objects are made of

the same material and have the same mass. However, the circular plate has the largest surface area, followed by the cube, and then the sphere. Therefore, the circular plate will cool the fastest, followed by the cube, and then the sphere.