Question
Please help with two true/false questions and one multiplechoice? 1. Rest masses can be expressed as units of energy 2. When an object approaches the speed of light, the objectwill stretch out in length but dimensions other than the directionof travel will remain the same. 3. A beam of light is shone forward from a moving vehicle. Thespeed of light leaving the vehicle will be: a.) dependent on the speed of the vehicle b.) the addition of the speed of light plus the speed of thevehicle c.) constant at the speed of light d.) slower so that the addition of the vehicle's speedcorrects it e.) none of the above Please help with two true/false questions and one multiplechoice? 1. Rest masses can be expressed as units of energy 2. When an object approaches the speed of light, the objectwill stretch out in length but dimensions other than the directionof travel will remain the same. 3. A beam of light is shone forward from a moving vehicle. Thespeed of light leaving the vehicle will be: a.) dependent on the speed of the vehicle b.) the addition of the speed of light plus the speed of thevehicle c.) constant at the speed of light d.) slower so that the addition of the vehicle's speedcorrects it e.) none of the above
Explanation / Answer
1. T Mass can be written as E /c2 where E is the total energy of theparticle. For mass moving at relativistic speed the relativistic mass isrelated to energy as above. The rest mass of the proton, for instance, can be written asmp = 931 Mev / c2 where Mev, an expression of energy, is in millions ofelectron-volts. 2. F An object moving at relativistic speeds appears shorterto an observer not in the "proper" frame where the "properframe" is the frame where the object is at rest. 3. c The speed of light is the same in allreference frames. where Mev, an expression of energy, is in millions ofelectron-volts. 2. F An object moving at relativistic speeds appears shorterto an observer not in the "proper" frame where the "properframe" is the frame where the object is at rest. 3. c The speed of light is the same in allreference frames.