A rigid of mass 2 kg is dropped from a stationary balloon kept at the height of 50 m from the ground. The speed of the body when it just touches the ground and the body when it just touches the ground and the total energy when it is dropped from the ballo

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Q: (NDA-II/2019)
A rigid of mass 2 kg is dropped from a stationary balloon kept at the height of 50 m from the ground. The speed of the body when it just touches the ground and the body when it just touches the ground and the total energy when it is dropped from the balloon are respectively. (acceleration due to gravity = 9.8 m/s 2)

question_subject: 

Science

question_exam: 

NDA-II

stats: 

0,1,3,2,1,0,1

keywords: 

{'stationary balloon': [0, 0, 0, 1], 'balloon': [0, 0, 0, 2], 'gravity': [0, 0, 0, 6], 'acceleration': [0, 0, 2, 8], 'mass': [0, 0, 2, 3], 'ground': [2, 1, 4, 17], 'total energy': [0, 0, 1, 4], 'speed': [0, 1, 2, 0], 'kg': [0, 1, 9, 24], 'height': [0, 0, 1, 2], 'body': [27, 3, 23, 37]}

Option 1 states that the speed of the body when it touches the ground is 980 m/s and the total energy is 980 J. This option is incorrect because the speed of the body when it touches the ground can be calculated using the formula v = sqrt(2gh), where v is the speed, g is the acceleration due to gravity, and h is the height from which the object is dropped. Plugging in the values, we get v = sqrt(2 * 9.8 * 50) = 31.3 m/s. Therefore, the speed of the body when it touches the ground is not 980 m/s.

Option 2 states that the speed of the body when it touches the ground is sqrt(980) m/s and the total energy is sqrt(980) J. This option is incorrect because the speed of the body when it touches the ground is 31.3 m/s as calculated before, and the total energy when the body is dropped from the balloon can be calculated using the formula E = mgh, where E is the total energy, m is the mass, g is the acceleration due to gravity, and h is the height from which the object is dropped. Plugging in the values, we get E =