1. Why gravitational force at the center of earth becomes zero through it is minimum distance from center of earth ?
2. Write three differences between conservative and non-conservative force with e.g. of these two types of forces?
3. Give a mathematical proof that all objects irrespective their mass slides downward on a frictionless inclined plane with same acceleration?
4. How a space shuttle orbiting araound the earth returns towards earth in the absence of any reaction force.
5. Calculate power produced by a force F = - 3i + j - 5k acting on a particle moving with velocity V = 4i + 3j - 5k.
6. What are Newton's rings ? How they are formed and derive experssion for radius of nth ring.
7. Two parallel slits are illuminated with lights of different wavelengths one of which is 6 X 10-9 on a nearby screen fourth dark line of known wavelength coincides with the fifth bright line of un known wavelength. Calculate this unknown wavelength.
8. A string 4m long resonates in four segments . The frequency of driving system is fond to be 120 hertz. Calculate the speed of the wave in the srring.
9. An electric fan rotating at 3 revolutions per second is swithed off. It comes to rest in 18s. Find its deceleration , how many revolutions did it makes before coming to rest.
10. A car starts from rest and moves with constant acceleration . During the 5th second of its motion it covers a distance of 36 meters . Calculate the distance of the car.