10. A fish looking up through the water sees the outside world in a circular horizon. Refractive index of water is 4/3 and the fish is 12 cm below the surface, radius of this circle in cm is,
9. A moving coil galvanometer has 150 equal divisions. Its current sensitivty is 10 divisions per milliampere and voltage sensitivity is 2 divisions per millivolt. In order that each division reads 1 volt, the resistance in ohms needed to be connected in series with the coil will be
8. The figure shows a system of two concentric spheres of radii r1 and r2 and kept at temperatures T1 and T2 respectively. The radial rate of flow of heat in a substance between the spheres is proportional to
7. A smooth block is released from rest on a 45 degrees incline and then slides a distance d. The time taken to slide is n times as much to slide on rough incline that on a smooth incline. the coefficient of friction is
6. An annular ring with inner and outer radii R1 and R2 is rolling without slipping with a uniform angular speed. The ratio of the forces experienced by the two particles situated on the inner and outer parts of the ring, F1/F2 is
5. A projectile can have the same range R for two angles of projection. If t1 and t2 be the time of flights in two cases, then the products of the two time of flights is proportional to
4. A particle is moving eastwards with a velocity of 5m/s. In 10s the velocity changes to 5m/s northwards. The average acceleration in this time is
3. A car starting from rest accelerates at the rate f through a distance S, then continues at constant speed for the time t, and then decelerates at the rate f/2 to come to rest. If the total distance traversed is 15S, then
2. The relation between time t and distance x is t= ax^2+bx where a and b are constants. The acceleration is
1. Out of the following pair, which one does not have identical dimensions is