# Physics

posted by
**Thaifa**
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1.(a) Explain the term time dilation.

(b) Show that an interval of time observed in a moving frame of reference will be less than the same interval of the observed in a stationary frame of reference.

2. A rocket was found to be 150m when measured on earth. It then leaves and move at a constant velocity of 2 x 10^8m/s. What is its new length?

3. Show that the force acting on a particle as observed by two observers in the two inertial frames if reference is the same. Given v<<c.

4. Two spaceships A and B are moving in opposite directions A with a speed of 0.9c while B with a speed of 0.6c. Find the relative velocity of B with respect to A.

5.A satellite goes round the earth in 90 minutes in a circular orbit. Calculate the height of the satellite above the earth taking the earth to be a sphere of radius 6370km. The value of g at the orbit of satellite is 9.8m/s^2