CBSE Guess > Papers > Important Questions > Class XI > 2007 > Physics > Mechanics of fluids Mr. Abhishek Gupta

Mechanics

Q. 1. A particle moves is the x-y plane with a velocity of 10i + 5j m/s and an acceleration of 2i m/s2. Find the distance covered in 1minute in X and in Y direction. Also find its velocity after 1 minute.

Q. 2. State the 3 laws of motion as given by Newton

Q. 3. Explain

1. A cricketer lowers his hand while catching the ball
2. A gun recoils when a bullet is fired

Q. 4. A ball is thrown with a speed of 100 m/s at an angle of 30o with the ground. Find the

1. Horizontal range
2. Time of flight
3. Maximum height gained
4. Velocity after 2 seconds of throwing
5. Velocity after 8 seconds of throwing

Q. 5. A 5Kg object is moving with a velocity of 10m/s in the x direction. A force of 50N acts on it for 5 seconds. Find the final velocity of the body if the direction of force is

1. Same as the direction of motion
2. Opposite to the direction of motion

Q. 6. 2 cars X and Y take part in a 100Km race. X moves half the distance with a speed of 40Km/hr and the remaining half of the distance with a speed of 60Km/hr . On the other hand Y moves with a speed of 60Km/hr for half the total time and with a speed of 40Km/hr for remaining half of the time. Find the time taken by each car and their average velocities.

Q. 7. A man is standing 50m behind a bus. The bus starts moving with a speed of 5m/s and in order to catch the bus the man starts moving with a speed of 10m/s. Find the time taken by the man to catch the bus. Also illustrate the solution with a position time graph.

Q. 8. Show that the range of a projectile is same if the angle of projection is 30o or 60o . In which case the range is more.

Q. 9. Two forces of 10N and 20N act on an object as shown in the figure. Find the resultant force and its 10 direction. The angle b/w the 2 given forces is 30^o

Q. 10. Draw position-time and velocity time graphs for

1. A stationary object
2. An object moving with a speed of 5m/s in the positive direction
3. An object moving with a speed of 5m/s in the negative direction
4. An object starting from rest and moving with an acceleration of 2m/s2
5. An object initially moving with 5m/s and then accelerating with 2m/s2