The star delta goes supernova. one year later and 2 ly away, as measured by astronomers in the galaxy, star epsilon explodes. let the explosion of delta be at xd=0 and td=0 . the explosions are observed by three spaceships cruising through the galaxy in the direction from delta to epsilon at velocities v1=0.3c, v2=0.5c and v3=0.7c.

1. what are the times of the two explosions as measured by scientists on each of the three spaceships? the times are given in years.
2.does one spaceship find that the explosions are simultaneous? if so, which one?
3. does one spaceship find that epsilon explodes before delta? if so, which one?
4. do your answers to parts b and c violate the idea of causality?

Acar of mass m goes around a banked curve of radius r with speed v. if the road is frictionless due to ice, the car can still negotiate the curve if the horizontal component of the normal force on the car from the road is equal in magnitude to 101) a) mv2/r b) mg/2. d) mg e) tan[v2/(eg)]

Aball is thrown upward. at a height of 10 meters above the ground, the ball has a potential energy of 50 joules (with the potential energy equal to zero at ground level) and is moving upward with a kinetic energy of 50 joules. what is the maximum height h reached by the ball? consider air friction to be negligible. 1. h ≈ 10 m 2. h ≈ 50 m 3. h ≈ 30 m 4. h ≈ 40 m 5. h ≈ 20 m 003 10.0 points which of the two object shown below has the greatest kinetic energy? a m b 1 2 m v 2v 1. kinetic energies are the same. 2. a 3. b 4. unable to determine. 004 10.0 points tim, with mass 74.6 kg, climbs a gymnasium rope a distance of 3.1 m. the acceleration of gravity is 9.8 m/s 2 . how much potential energy does tim gain? answer in units of j. 005 10.0 points a car is moving at 64 miles per hour. the kinetic energy of that car is 5 × 105 j. how much energy does the same car have when it moves at 111 miles per hour? answer in units of j. 006 10.0 points an 102 kg man climbs up a 1 m high flight of stairs. the acceleration of gravity is 9.81 m/s 2 . w

Which of the following is an example of motion in two dimensions?