During _____________ motion of an object along a straight line, the velocity remains constant with time and equal distances are covered in equal intervals of time.

Introduction / Context:
Classifying motion involves looking at how an object position and velocity change over time. When an object moves along a straight line with constant velocity, it is an important special case used in many physics problems and definitions. This question asks which term best describes motion in which velocity remains constant with time along a straight line.

Given Data / Assumptions:

• The object moves along a straight line path.
• Velocity remains constant in magnitude and direction with time.
• Equal distances are covered in equal intervals of time.
• We choose from terms linear, translational, uniform and equilibrium.

Concept / Approach:
Uniform motion is defined as motion in which an object covers equal distances in equal intervals of time along a straight line. This implies constant velocity. Linear motion refers to motion along a straight path but does not specify whether speed is constant or changing. Translational motion means that all points of a body move in parallel paths; this can occur with variable speed, so it is not automatically constant velocity. Equilibrium refers to a state where net force is zero, which implies constant velocity but does not specifically describe motion pattern in the same way. The correct term that directly captures constant velocity in a straight line is uniform motion.

Step-by-Step Solution:
Step 1: Recall the definition of uniform motion: equal distances covered in equal time intervals in a straight line.Step 2: Relate constant velocity to equal distances per equal times; if velocity is constant, speed and direction do not change.Step 3: Recognise that this matches exactly the description of uniform motion.Step 4: Note that linear motion describes the path shape but not constancy of speed.Step 5: Note that translational motion describes overall body movement and can be non uniform or uniform.Step 6: Equilibrium is a condition on forces, not the standard descriptive term for this distance time pattern.Step 7: Conclude that uniform motion is the correct completion of the sentence.

Verification / Alternative check:
A car moving at a constant 60 km/h in a straight line on a highway is in uniform motion. In every 10 minutes, it covers the same distance. This situation is best described as uniform motion rather than simply linear or translational, because those words do not highlight the constancy of velocity. While it is true that such a car is also in translational motion and its forces may sum to zero, the special term uniform motion is what textbooks use for equal distances in equal times.

Why Other Options Are Wrong:
Linear motion could be uniform or non uniform depending on whether speed changes, so it is too general. Translational motion is also general and does not imply constant speed. Equilibrium, while related to balanced forces, is not the phrase normally used in the definition given in the question and can apply even when motion is not along a simple straight line segment. Therefore, uniform is the best and standard answer.

Common Pitfalls:
Students sometimes choose linear because they focus only on the straight line part of the description and ignore the constant velocity condition. Others may be attracted to translational because it sounds technical. To avoid such errors, always match the entire description, including the equal distances in equal times, with the definition of uniform motion.

Final Answer:
When velocity remains constant along a straight line, the motion is called uniform motion.