Homework Help: Physics

Posted by Jordan Stark on Monday, July 9, 2012 at 4:55pm.

A spaceship and its occupants have a total mass of 170000kg . The occupants would like to travel to a star that is 31 light-years away at a speed of 0.40c. To accelerate, the engine of the spaceship changes mass directly to energy.

How much mass will be converted to energy to accelerate the spaceship to this speed? Assume the acceleration is rapid, so the speed for the entire trip can be taken to be 0.40c, and ignore decrease in total mass for the calculation.

Physics - drwls, Tuesday, July 10, 2012 at 7:24am
Compute the increase in kinetic energy desired. Divide that by c^2 for the mass loss required.

You will be accurate enough if you use (1/2) M V^2 for the kinetic energy required. For V, assume 0.4c

Delta M = (1/2) M V^2/c^2 = (1/2)M*0.16c^2/c^2
= 0.08 M

You don't need to use the 31 light year distance.
Physics - Jordan Stark, Wednesday, July 11, 2012 at 12:22pm
I tried that and it didn't work at all

Answer this Question

Related Questions

physics - At what rate must a cylindrical spaceship rotate if occupants are to ...
physics - At what rate must a cylindrical spaceship rotate if occupants are to ...
physics - several students are riding in bumper cars at an amusement park. the ...
physics - At what rate must a cylindrical spaceshiprotate if occupants are to ...
Physics - A spacecraft in the shape of a long cylinder has a length of 100 m, ...
Physicssssss - At what rate must the cylindrical spaceship of Fig. 5-30 rotate (...
Physics - At what rate must a cylindrical spaceship rotate if occupants ar to ...
Physics - A Ferris wheel has a radius of 14 m. What period of rotation would ...
Science - Physics - How can I investigate what happens to the occupants of a car...
physics - a hot air balloon rise above the ground, accelerating upwards at a ...

For Further Reading

First Name:
School Subject:
Answer: