Question

5. When is this equation valid? (1 + ε)" ~ 1 + n ε A) For massless particles, but not massive B) For large values ofn C) For time dilation but not length contraction D) For e very small E) This formula is always valid 6. According to the conventions I used in relativity, which of the following does not become large as velocity approaches the speed of light? A) Energy B) Momentum C) Mass D) The Lorentz factor γ E) Actually, all of these do become large 7. Under what circumstances is the approximation γ=1 most useful? A) When v is negative B) When v is positive C) When v>c D)When v << c E) This is always true 8. When an object passes us at high velocity in the x-direction, an observer will see it get shorter A) In all three dimensions (x, y, and z) B) In the x-direction, but not in the y- or z-direction C) In the y- or z-direction, but not in thex-direction D) In no dimension; only observers moving with the object will see it getting shorter E) In no dimension; moving object looks longer, not shorter 9. A light source is moving at speed c to the right. It shoots out a light beam perpendicular to its direction of motion, as viewed by it. The speed of the light beam, as viewed by us, will be A)1/2c B) 3/2 c C) V3/2 c D) V5/2 c

Answer 1

5) C (in time dilation we used this because we have $\sqrt{1 -v\: ^{2}/c^{2}}$ in the denominator)

6) E (every quantity will increase)

7) C (in this condition denominator becomes imaginary that's why we take $\gamma$ = 1)

8) B (we can see the object in x - direction )

9) E (by using velocity addition we can find it is c)