Final answer:
The kinetic energy when the height is 2 m is 19.6 J. option c
Step-by-step explanation:
The formula to calculate the kinetic energy (KE) of an object at a certain height in a gravitational field is given by KE = mgh, where m represents the mass of the object, g is the acceleration due to gravity, and h denotes the height.
Given the height h = 2 m, we need to consider the potential energy (PE) at this height first. PE = mgh, and at a height of 2 m, the potential energy is PE = mg * 2.
Now, according to the law of conservation of energy, at this height, all the potential energy is converted into kinetic energy when the object falls freely. Therefore, the potential energy at a height of 2 m will be equal to the kinetic energy at the same height.
Considering the mass and the gravitational acceleration (assuming g = 9.8 m/s²), we calculate the kinetic energy using KE = mgh, which translates to KE = m * 9.8 * 2. Assuming the mass is 1 kg, the kinetic energy at 2 m height is 19.6 J. Therefore, the correct answer among the options provided would be C) 19.6 J.