**Correct Option: C. The gravitational field strength increases as you move closer to the object.** ### Detailed Explanation: 1. **Understanding Gravitational Field Strength:** - The gravitational field strength (g) at a distance (r) from a massive object, like Earth, is defined by the formula: \[ g = \frac{GM}{r^2} \] where: - \( G \) is the gravitational constant (\( 6.674 \times 10^{-11} \, \text{N m}^2/\text{kg}^2 \)), - \( M \) is the mass of the object (e.g., Earth), - \( r \) is the distance from the center of the object to the point where the field strength is being measured. 2. **Analyzing the Formula:** - From the formula, we can see that gravitational field strength \( g \) is inversely proportional to the square of the distance \( r \). This means that as \( r \) decreases (i.e., as you move closer to the massive object), the value of \( g \) increases. - For example, if you were to move from a distance of 10,000 km from the center of the Earth to 6,000 km, the gravitational field strength would increase significantly because you are reducing the distance \( r \). 3. **Why Option C is Correct:** - As you approach a massive object like Earth, the gravitational pull you experience becomes stronger. This is because the gravitational force is concentrated over a smaller area as you get closer, leading to an increase in gravitational field strength. ### Why the Other Options are Incorrect: - **Option A: The gravitational field strength decreases as you move closer to the object.** - This statement is incorrect because, as explained, the gravitational field strength actually increases as you move closer to the object. The inverse square relationship indicates that a decrease in distance results in an increase in gravitational field strength. - **Option B: The gravitational field is uniform and has the same strength at all distances from the object.** - This statement is also incorrect. The gravitational field is not uniform; it varies with distance from the mass. Near the surface of the Earth, the field can be approximated as uniform over small distances, but it is not the case at larger distances. - **Option D: The gravitational field only exists at the surface of the object and not in the surrounding space.** - This statement is false. The gravitational field exists in the space surrounding a massive object, not just at its surface. In fact, the gravitational influence of an object extends infinitely, although it weakens with distance. ### Common Pitfalls: - Students often confuse the concept of gravitational field strength with gravitational force. Remember that gravitational field strength is a property of the field itself, while gravitational force is the interaction between two masses. - It’s important to visualize the gravitational field lines, which point towards the mass and indicate the direction of the gravitational force. The density of these lines represents the strength of the field; they are closer together near the mass and spread out further away. ### Revision Summary: - Gravitational field strength increases as you move closer to a massive object due to the inverse square law. - The formula for gravitational field strength is \( g = \frac{GM}{r^2} \). - The gravitational field exists in the space surrounding a mass, not just at its surface. - Understanding the difference between gravitational field strength and gravitational force is crucial for solving related problems.