A man weighs 645 N on Earth. What is his mass?
To find the man's mass, we need to use Newton's second law of motion, which states that the weight of an object is equal to its mass multiplied by the acceleration due to gravity.
Weight (W) = Mass (m) × Acceleration due to gravity (g)
On Earth, the acceleration due to gravity is approximately 9.8 m/s².
Given that the man's weight is 645 N, we can plug these values into the equation to solve for his mass:
645 N = m × 9.8 m/s²
To find the man's mass, divide both sides of the equation by 9.8 m/s²:
m = 645 N / 9.8 m/s²
Calculating this, we find:
m ≈ 65.82 kg
Therefore, the man's mass is approximately 65.82 kilograms.