A body is released from the top of a tower '$$\mathrm{H}$$' metre high. It takes $$t$$ second to reach the ground. The height of the body $$\frac{t}{2}$$ second after release is

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