Laws of Motion ...

A curved road of 50 m in radius is banked to correct angle for a given speed. If the speed is to be doubled keeping the same banking angle, the radius of curvature of the road should be changed to

It is easier to pull a body than to push, because-

A fighter plane is pulling out for a dive at a speed of 9 km/hr. Assuming its path to be a vertical circle of radius 2000 m and its mass to be 16000 kg, find the upward force extended by air on it at the lowest point.Take g =$$9.8 m/s^{2}$$

Race car A follows path abcde while race car $$ \mathrm{B}  $$ follows path12 $$ \mathrm{c} 34  $$ track. If each car has a constant speed corresponding to a normal acceleration of 8 $$ \mathrm{m} / \mathrm{s}^{2}  $$ . The tracks abcde and 2 $$ \mathrm{c} 3  $$ are semicircular track while tracks $$  1-2  $$and $$ 3-4  $$ are straight track. Point a and point 1 are the starting points of race and point 4 and point e are finishing points of the race choose the correct statements.

A vessel filled with water is placed on the edge of a board as shown in figure. A small board carrying some weight is placed on the water surface. Then choose the correct statement -

The maximum and minimum tensions in a string of length 0.1 m with a stone 5 g tied to it and whirled in a vertical circle are in the ratio 13 : 1. The velocity of the body at highest point is 

Total impulse imposed by ball of mass 2 kg to the ball of mass 4 kg has the magnitude equal to 

A 20 g bullet pierces through a plate of mass $${ m }_{ 1 }=1$$ kg and then comes to rest inside a second plate of mass $${ m }_{ 2 }=2.98$$ kg. It is found that the two plates, initially at rest, now move with equal velocities. The percentage loss in the initial velocity of bullet when it is in between the plates is (neglect any loss of material due to action of bullet) 

A car of mass $$1500kg$$ takes a turn of a curved road of radius $$300m$$ with a speed of $$9m/s$$. The centripetal force acting on the car is:

The radius of curvature of a road at a certain turn is 50m. The width of the road is 10m and its outer edge is 1.5m higher than the inner edge. The safe speed for such an inclination will be