Final answer:
To calculate the tension in the string, we use the centripetal force formula. We convert revolutions per second to velocity in meters per second and then substitute into the centripetal force formula. Applying SI unit conversions and principles of circular motion, we can find the tension experienced by the stone.
Step-by-step explanation:
The problem given involves calculating the tension in a string when a stone of mass 20 g is whirled in a horizontal circle. The stone makes 4 revolutions per second, and the length of the string is 2.0 m. Since the stone is in a horizontal circle and the other end of the string is stationary, we can calculate the tension using the formula for centripetal force, which is Fc = m*v2/r, where m is the mass, v is the velocity, and r is the radius of the circle.
First, we need to convert revolutions per second to meters per second to get the velocity. Since the stone makes 4 revolutions per second (which we'll denote as f), and each revolution covers a distance equal to the circumference of the circle (2πr), we calculate the velocity v as v = 2πr*f. After calculating the velocity, we substitute it into the centripetal force formula to find the tension in the string, which is the same as the centripetal force in this scenario because the circular motion keeps the string taut.
Using the given values and the SI unit conversion for mass from grams to kilograms (20 g = 0.02 kg), the final step is to perform the calculations to find the tension. Through this process, we apply principles of circular motion and dynamics to solve for the tension experienced by the whirling stone.