A mass of 10kg moves down with uniform speed of 2m/s. Its air resistance will be
Correct answer: B. 100 N
- A. 10 N
- B. 100 N
- C. 0
- D. 20 N
Explanation
Since the object is moving at a constant speed, the net force acting on it must be zero. This means the downward gravitational force is balanced by an equal upward force, which in this case is the air resistance. The gravitational force acting on the object is calculated as mass (10 kg) times gravity (approximately 10 m/s²), giving us 100 N. Therefore, the air resistance is also 100 N. The other options are incorrect as they do not correctly balance the gravitational force.
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