GS5. Which of the following is a greenhouse gas? University Of Sindh mcqs test

 

MOTION IN TWO DIMENSION

(PROBLEMS)

1. A rescue helicopter drops a package of emergency ration to a stranded party on the ground. If the helicopter is traveling horizontally at 40m/s at a height of 100m above the ground. (a) where does the package strike the ground relative to the point at which it was released? (b) What are the horizontal and vertical component of the velocity of the package just before it hits the ground?

2. A long-jumper leaves the ground at an angle of 20° to the horizontal and at a speed of 11m/s (a) How far does he jump? What is the maximum height reached? Assume the motion f the long jumper is that of projectile.

3. A stone is thrown upward from the top of a building at an angle of 30 to the horizontal and with a initial speed of 20m/s. If the height of building is 45m. (a) the speed of stone just before it strikes the ground? (c) Where does the stone strike the ground?

4. A ball is thrown in the horizontal direction from a height of 10m with a velocity of 21m/s (a) How far will it hit the ground from its initial position on the ground? and with what velocity?

5. A rocket is launched at an angle of 53° to the horizontal with an initial speed of 100 m/s. It moves along its initial line of motion with an acceleration of 30 m/s² for 3s. At this time the engine fails and the rocket proceeds to move as a free body. Find (a) the maximum altitude reached by the rocket (b) its total time of flight, and (c) its horizontal range.

6. A driver leaps from a tower with an initial horizontal velocity component of 7m/s and upward velocity component of 3m/s. Find the component of her position and velocity after 1 second.

7. A boy standing 10 m from a building can just barely reach the roof 12 m above him when he throws a ball at 132 the optimum angle with respect to the ground. Find the Initial velocity component of the ball.

8. A marter shell is fired at a ground-level target 500 m distance with an initial velocity of 90 m/s. What is its launch angle?

9. What is the take-off speed of a locust if its launch angle is 55° and its range is 0.8m?

10. A car is traveling on a flat circular track of radius 200 m at 20 m s' and has a centripetal acceleration a = 4.5 m/s2 (a) If the mass of the car is 1000 kg, what frictional force is required to provide the acceleration? (b) If the coefficient of static friction is is 0.8, what is the maximum speed at which the car can circle the track?

11. The turntable of a record player rotates initially at a rate of 33 rev/min and takes 20 s to come to rest (a) What is the angular acceleration of the turntable, assuming the acceleration is constant? (b) How many rotations does the turntable make before coming to rest? (c) If the radius of the turntable is 0.14 m, what is the initial linear speed of a bug riding on the rim? (d) What is the magnitude of the tangential acceleration of the bug at time t=0?

12. Tarzan swings on a vine of length 4m in a vertical circle under the influence of gravity. When the vine makes an angle of 0 = 20° with the vertical, Tarzan has a speed of 5m/s. Find (a) his centripetal acceleration at this instant, (b) his tangential acceleration, and (c) the resultant acceleration.