1. A boy standing on a long railroad car throws a ball straight upwards. The car is moving on the horizontal road with an acceleration of 1m/s^2 and the projection velocity in the vertical direction is 9.8m/s. How far behind the boy will the ball fall on the car? (Ans:2m)
2. A person standing on top of a cliff 171ft high has to throw a packet to his friend standing on the ground 228ft horizontally away. If he throws the packet directly aiming at his friend, with a speed of 15ft/s, how short will the packet fall? (Ans:192ft)
3. A shell is fired horizontally with a velocity of 200m/s from the top of a tower. It hits a target on the ground after 2s. (i) what is the height of the tower? (ii)Where is the target situated? (iii) with what vertical velocity does the shell strike the target? (Ans:19.6m, 400m, 19.6m/s)
4. From the top of a building 19.6m high, a ball is projected horizontally. After how long will the ball strike the ground? If the line joining the point of projection to the point where it strikes the ground is 60degree with the horizontal, what is the velocity with which the ball is projected? (Ans: 2s, 5.65m/s)
5. A ball is projected horizontally with a velocity of 5m/s. Find the position and velocity after 0.25s. (Ans: 1.29m, 5.57m/s)
6. A man can swim at a speed of 3km/h in still water. He wants to croos a 500m wide river flowing at 2km/h. He keeps himself always at an angle of 120degrees with the river flow while swimming. Find (a)the time he takes to cross the river. (b) at what point on the opposite bank will he arrive? (Ans: 1/3 sq.root3 h , 1/6 sq.root3km)
2. A person standing on top of a cliff 171ft high has to throw a packet to his friend standing on the ground 228ft horizontally away. If he throws the packet directly aiming at his friend, with a speed of 15ft/s, how short will the packet fall? (Ans:192ft)
3. A shell is fired horizontally with a velocity of 200m/s from the top of a tower. It hits a target on the ground after 2s. (i) what is the height of the tower? (ii)Where is the target situated? (iii) with what vertical velocity does the shell strike the target? (Ans:19.6m, 400m, 19.6m/s)
4. From the top of a building 19.6m high, a ball is projected horizontally. After how long will the ball strike the ground? If the line joining the point of projection to the point where it strikes the ground is 60degree with the horizontal, what is the velocity with which the ball is projected? (Ans: 2s, 5.65m/s)
5. A ball is projected horizontally with a velocity of 5m/s. Find the position and velocity after 0.25s. (Ans: 1.29m, 5.57m/s)
6. A man can swim at a speed of 3km/h in still water. He wants to croos a 500m wide river flowing at 2km/h. He keeps himself always at an angle of 120degrees with the river flow while swimming. Find (a)the time he takes to cross the river. (b) at what point on the opposite bank will he arrive? (Ans: 1/3 sq.root3 h , 1/6 sq.root3km)
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