Final answer:
The mass of the iron weight can be calculated using the tension in the string which is equal to the weight of the mass. The mass is approximately 0.485 kilograms.
Step-by-step explanation:
The question asks for the mass of an iron weight suspended by a string, where the tension in the string is 4.75 newtons. To find the mass of the iron weight, we need to use the relation between the tension T and the weight of the mass W, which is given by W = mg, where m is the mass and g is the acceleration due to gravity (approximately 9.8 m/s²). Since the weight is motionless, it is in static equilibrium, hence the tension in the string is equal to the weight of the iron weight (T = W).
Using the formula to find the mass, we rearrange the equation: m = T/g. Plugging in the values, we have m = 4.75 N / 9.8 m/s². Calculating this gives us the mass m of the iron weight, which would be approximately 0.485 kilograms.
It can also be helpful to refer to similar problems that deal with the concept of tension, such as the pendulum example and the tightrope walker example, to better understand the relationship between mass, gravity, and tension.