Question no 21

Question no 21 IS. Describe the nature of force acting in the above shown displacement — time graph. 16. State Newton's second law of motion and show 'hat the law Of motion can be mathematical expression for the second law of motion 17. Observe the lime graph given for the ball mass 20! which moves along a straight linc Calculate the force exerted by the surface 10 bring it to rest. 15 Time 'sj 18. (a) Write the units Of momentum.(b) Which quantity should be varied if momentum ofa body of given mass needs to be A constanl force applied on an object of n.ass 2 Kg ror 10s, increases its velocity from im's to 10mis, Find the magnitude Of applied force. If the Saane force is applied [Or 15s. What Will be the final velocity Of the Object? A stone released from the top Ofa toner height 1 9.6m. Calculate its final velocity just before touching ground, (Take a— IOnÜs2) 20. A man weighting 60kg runs along the rails with a velocity of 18 Km/h and jumps into a car of mass Iquintal (100 Kg) standing on the rails Calculate the velocity with which the car will Start travelling along the rails 21 Two carts A and B of mass 10kgeach are placed on a horizontal track. Ihey are joined tightly by a strong rope. a man can hold the cart and pulls it towards right with torce of90N. The total for•k' of friction by the track and the air on each mass is I SN acting towards the left. Find a. "he acceleration or the carts b. The force exerted by the rope on the cart B 22. Car A Of mass 1500 kg travelling at 25 my's collides with another car B of mass 1000 kg travelling at J 5 m/s in the same direction. After collision. the velocity of Car A becomes 20 m/s, Calculate the velocity ofCar B after collision?