Two observers are moving relative to one another at a speed v along a straight line. They watch a block of mass m travelling a distance l over a rough surface. Which of the following quantities will be identical as measured by the two observers?

Step-by-step solution

Since the two observers are moving relative to each other at a constant speed v , they are in different inertial frames of reference. According to Galilean relativity, the acceleration of an object is invariant across all inertial frames. If u and u' are the velocities of the block measured by the two observers, they are related by u' = u - v . Differentiating with respect to time t , we get du' dt = du dt since v is constant. Thus, a' = a . The displacement of the block depends on the frame of reference. Consequen