A shell is fired at an angle of $$30^{\circ}$$ to the horizontal with velocity $$196 \mathrm{~m} / \mathrm{s}$$. The time of flight is

$$\left[\sin 30^{\circ}=\frac{1}{2}=\cos 60^{\circ}\right]$$

A student is throwing balls vertically upwards such that he throws the $$2^{\text {nd }}$$ ball when the $$1^{\text {st }}$$ ball reaches maximum height. If he throws balls at an interval of 3 second, the maximum height of the balls is $$\left(\mathrm{g}=10 \frac{\mathrm{m}}{\mathrm{s}^2}\right)$$

A driver applies the brakes on seeing the red traffic signal $$400 \mathrm{~m}$$ ahead. At the time of applying the brakes, the vehicle was moving with $$15 \mathrm{~m} / \mathrm{s}$$ and retarding at $$0.3 \mathrm{~m} / \mathrm{s}^2$$. The distance covered by the vehicle from the traffic light 1 minute after the application of brakes is

A body at rest falls through a height 'h' with velocity 'V'. If it has to fall down further for its velocity to become three times, the distance travelled in that interval is