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$A bomber dropped a bomb at a height of 490 \mathrm{~m} when its velocity along the horizontal was 300 \mathrm{kmh}^{-1} .(a) At what distance from the point vertically below the bomber at the instant bomb was dropped did it strike the ground?$  $A boy places a fire cracker of negligible mass in an empty can of 40 \mathrm{~g} mass. He plugs the end with a wooden block of mass 200 \mathrm{~g} . After igniting the firecracker he throws the can straight up. It explodes at the top of its path. If the block shoots out with a speed of 3 \mathrm{~ms}^{-1} how fast will the can be going?$  $Explain the circumstances in which the velocity " v " and acceleration "a" of a car are:(iv) " v " " is zero but "a" is not$  $Explain the circumstances in which the velocity " v " and acceleration "a" of a car are:(v) "a" is zero but " v " is not zero$  $A hose pipe ejects water at a speed of 0.3 \mathrm{~ms}^{-1} through a hole of area 50 \mathrm{~cm}^{2} . If the water strikes a wall normally calculate the force on the wall assuming the velocity of the water normal to the wall is zero after striking.$  $Each of the following questions is followed by four answers one of which is correct answer. Identified that answer.(i) What is meant by a ballistic trajectory?(a) The paths followed by an un-powered and unguided projectile is called ballistic trajectory.(b) The path followed by the powered and unguided projectile is called ballistic trajectory.(c) The path followed by un-powered but guided projectile.(d) The path followed by powered and guided projectile.$  $A 1500 kg car has its velocity reduced from 20 \mathrm{~ms}^{-1} to 15 \mathrm{~ms}^{-1} in 3 . S . How large was the average retarding force.$  