Is there still relativity on the Physics SAT?

<p>If there is, how much of it is covered?</p>

<p>Anyone who took the test this year - how many relativity questions were there and what was their difficulty?</p>

<p>Easy questions, concept based or equation plug in. Honestly relativity is one of the easiest things to get on physics there is no reason to miss any relativity based questions.</p>

<p>It's all relative to the test.</p>

<p>^ haha what a dork ;D</p>

<p>Ok, so I guess the answer's yes.</p>

<p>Here are stuff for practice:</p>

<p>When a spaceship reaches relativistic speeds, and it is seen by an stationary observer for a given time interval, does it seen to go through a greater distance than recorded by the spaceship (time gets dilated, velocity stays the same), or a lower velocity than recorded by the spaceship (time gets dilated, distance stays the same)?</p>

<p>When a person in the spaceship looks at a clock on earth, does it seem to go faster or slower?</p>

<p>1) Yes, the observer's recorded distance is greater than the astronaut's recorded distance.
2) The clock seems to move faster to the astronaut.</p>

<p>The clock moves slower, because in the astronaut's reference frame he is still while the earth moves past him at nearly the speed of light. There is no reference frame in which time is accelerated, only dilated.</p>

<p>Yea you're right.</p>

<p>I dont understand israelxwired's question? think u could explain in more detail? thanks. and meteman said it is "plug-in": what equation do we need to "plug in"to? thanks</p>

<p>Length and Time go to 0 while Mass and KE go to infinity as the speed of an object approach c. </p>

<p>There are equations but we definitely wont have to plug in w/o a calculator. The questions will be mostly conceptual.</p>

<p>Correct me if I'm wrong but doesn't time go to infinity? Assuming the equation is set up with proper time already known.</p>

<p>A cabbage-loving sheep is launched on a spaceship travelling at a speed of (4/5)c toward a distant star. After 15 years according to the sheep, the star is reached. How far away in light-years is the star from Earth?</p>

<p>a) 7.2
b) 9.0
c) 12
d) 20
e) 25</p>

<p>c) 12?

<p>No, don't forget that the sheep clock rate is different than the earth clock rate, at least for observers on the earth.</p>

<p>Not that sheep have bad clocks in general of course, just for this problem :)</p>

<p>Huh. So basically, if I haven't covered relativity yet, I'm screwed? Or can I just learn them on my own though the use of the prep books? (I have til October).</p>

<p>^Prep books should be fine, relativity is really a pretty minor topic: it is just a piece of a the 10% of the test devoted to modern physics.</p>