Question

QUESTION 2
1.   Two people in different inertial reference frames are observing a ball as it moves through the air. One person claims to observe the ball to go straight up and then straight down. The other person claims to observe the ball to move in a parabolic path. What can we say about these two claims?

a.   These two claims are mutually incompatible. The ball follows only a single path. Either it goes in a straight line up and down or it goes in a parabolic path. It cannot go in both paths simultaneously.

b.   These two claims are mutually incompatible. One of the observers is purposely lying.

c.   These two claims are mutually incompatible. One observer needs to have an eye examination to check for a vision problem.

d.   These two claims are compatible and are consistent with the laws of physics.

QUESTION 3
1.   Person A is riding in a high speed train car which also contains two flashlamps (one in the front of the train car and one in the back of the train car). The train car has a constant velocity of 150 km/hr south. The two flashlamps are equidistant from Person A. Both of the lamps give off a flash of light that arrive at Person A simultaneously. Person B is standing beside the train track and observes person A and the two lamps. Will Person B observe the two flashes of light to arrive simultaneously at Person A?

a.   Yes

b.   No

c.   Don't select this answer.

d.   Don't select this answer.      

QUESTION 11
1.   Super Physics Dude is training for the Super Olympics and is able to run really fast. He can run at 0.806 c (where c is the speed of light which is 3.00 X 10^8 m/s). He is trying to impress his friend Super Chemistry Lady and waves at her as run past at 0.806 c. He measures each of his waves to take 1.00 seconds. How long does Super Chemistry Lady measure for each wave?

   1.00 seconds

   0.592 seconds

   1.69 seconds

   2.27 seconds

Answer 1

Genererally to avoid such ambiguity we choose the frame of reference according to which we will define the motion of the body. But there is no hard and first rule about this choice. Like in the above given example we can tell that the path of the body is a straight line with respect to B or we may tell parabola with respect to C.

Note: if we choose moving reference frame then we have to use pseudo force in the direction opposite to the actual motion of the body.