A nuclear explosion on Earth generates an electromagnetic pulse that travels away from the Earth. A long distance from Earth, scientists on an alien planet named Tutheleftaya, a distance LL from the Earth, detect the pulse. Since the pulse travels at the speed of light, they detect it at time t=L/ct=L/c after the pulse was created on Earth. Another group of scientists on another alien planet, named Offtatheright, which is also a distance LL away from the Earth, but in the opposite direction, also detect the pulse. Since they are the same distance from the Earth, they detect it at the same time as the scientists on Tutheleftaya. In the reference frame of someone traveling on a spaceship going from the Earth to Tutheleftaya, and about halfway there when the explosion happens, which group of scientists detects the pulse first?

Jason and mia are both running in a race. as they approach the finish line, you being the physicist that you are decide to time how long it takes them to reach the end of the race. when you start your stop watch (you can take this as time t = 0 s) you notice that mia is an unknown distance d ahead of jason and both are moving with the same initial velocity v_0. you also notice that jason is accelerating at a constant rate of a_j, while mia is deaccelerating at a constant rate of -a_m. jason and mia meet each other for the first time at time t = t_1. at this time (t = t_1) jason's velocity is two times that of mia's velocity, meaning v_j (t_1) = 2v_m (t_1). a) draw the position vs. time graph describing mia's and jason's motion from time t = 0 to time t = t_1. clearly label your axes and initial conditions on your graph. b) draw the velocity vs. time graph describing mia and jason's motion from time t = 0s to time t = t_1. clearly label your axes and initial conditions on your graph. c) how long from when the stop watch was started at t = 0s did it take mia and jason to meet? express your answer in terms of know quantities v_0, a_m, and a_j. d) when the stop watch started at time t = 0s, how far apart, d, were mia and jason? express your answer in terms of know quantities v_0, a_m, and a_j.

In a stagnant pool of water, a crayfish may spend much of its time lying with one side of its carapace near the surface of the water. in this position, it will move the walking legs on that side in a rhythmic back-and-forth motion. explain the likely function of this behavior.

What are the necessary conditions for fusion?