A tennis ball is dropped on to the floor from a height of 9.8 m. It rebounds to a height 5.0 m. Ball comes in contact with the floor for 0.2s. The average acceleration during contact is ___________ ms$$^{-2}$$.

(Given g = 10 ms$$^{-2}$$)

A ball is thrown vertically upwards with a velocity of $$19.6 \mathrm{~ms}^{-1}$$ from the top of a tower. The ball strikes the ground after $$6 \mathrm{~s}$$. The height from the ground up to which the ball can rise will be $$\left(\frac{k}{5}\right) \mathrm{m}$$. The value of $$\mathrm{k}$$ is __________. (use $$\mathrm{g}=9.8 \mathrm{~m} / \mathrm{s}^{2}$$)

A particle is moving in a straight line such that its velocity is increasing at 5 ms^{$$-$$1} per meter. The acceleration of the particle is _____________ ms^{$$-$$2} at a point where its velocity is 20 ms^{$$-$$1}.

A car is moving with speed of $$150 \mathrm{~km} / \mathrm{h}$$ and after applying the break it will move $$27 \mathrm{~m}$$ before it stops. If the same car is moving with a speed of one third the reported speed then it will stop after travelling ___________ m distance.