You are standing on the roadside watching a bus passing by A

You are standing on the roadside watching a bus passing by. A clock is on the Bus. Both you and a passenger on the bus are looking at the clock on the bus, and measure the length of the bus. Who measures the proper time of the clock on the bus and who measures the proper length of the bus? You measure the proper time of the clock on the bus, and the passenger measures the proper length of the bus The passenger measures both the proper time of the clock on the bus and the proper length of the bus You measure both the proper time of the clock on the bus and the proper length of the bus The passenger measures the proper time of the clock on the bus, and you measure the proper length of the bus Which one or more of the following quantities will two inertial observers always measure to be the same, regardless of the relative motion between the two observers? The relative speed between the two observers The speed of light in a vacuum The time interval between two events The length of an object

Solution

Q2. The length of the bus gets contracted and time gets dialated to me. So the passenger who is in the frame of the bus should be able to measure both accurately.

Q3. The speed of light is universal and does not change under any circumstances. So the observer should be able to measure spped of light and their relative velocity correctly.