CLASS 11 - ASSIGNMENT 4 - MOTION IN A STRAIGHT LINE

 MOTION IN A STRAIGHT LINE

CLASS 11

ASSIGNMENT 4

1. What is mechanics?

2. Define rest and motion.  Show that they are relative terms.

3. What are the various sub-branches of mechanics?

4. Is it true that a body is at rest in a frame within which it has been fixed?

5. Under what condition can an object in motion be considered a point object?

6. Give an example of a physical phenomenon in which earth cannot be regarded as a point mass.

7.  Define (i) one dimensional motion

                  (ii) two dimensional motion

                  (iii) three dimensional motion

8. Distinguish between distance and displacement.

9. Mention some important characteristics of displacement.

10. Under what condition will the distance and displacement of moving object have the same magnitude?

11. A particle is moving along a circular track of radius r.  What is the distance traversed by the particle in half revolution?  What is its displacement?

12. Will the displacement of an object change on shifting the position  of origin of the coordinate system?

13.  Define speed.  Give its units and dimensions.

14. What are the different types of speed?

15. Is speed a vector or scalar quantity?

16.  Define velocity.  Give its units and dimensions.

17.  What are the different types of velocities?

18.  Is velocity a scalar or vector quantity?

19.  Define uniform motion.

20.  Define (i) uniform speed  (ii) variable speed  (iii) average speed  (iv) instantaneous speed  (v) uniform velocity  (vi) variable velocity  (vii) average velocity  (viii) instantaneous velocity

21.  Obtain the formula for the position of an object moving with uniform velocity v (i) at any time t in terms of its position at t=0 and (ii) at any time tٰ₁ in terms of its position at another time t.

22. What does the speedometer of a car measure?

23.  What is the numerical value of velocity to speed of an object?

24.  If the displacement of a body is zero, is the distance covered by it necessarily zero?  Comment with suitable illustration.

25. Can a body have a constant speed and still have a varying velocity?

26.  What is non-uniform motion?

27.  Define acceleration.  Give its units and dimensions.  Is it a scalar or vector quantity?

28.  What are the different types of acceleration? Define each one of them.

29. What are positive and negative accelerations?

30. Derive the 4 equations of motion for an object moving with constant acceleration along a straight line.

31.  Deduce the 4 equations of motion for uniformly accelerated motion using integration technique.

32.  Discuss the motion under free fall.  Write the equations of motion for a freely falling object.

33.  Is it possible that your cycle has a northward velocity but southward acceleration?  If yes, how?

34.  Why does time occur twice in the unit of acceleration?

35.  Is the acceleration of a car greater when the accelerator is pushed to the floor or when brake pedal is pushed hard?

36.  Can a particle with zero acceleration speed up?

37.  State the condition when the magnitude of velocity and speed of an object are equal.

38.  Read each of the following and state with reasons and examples whether it is true or false.  A particle in one-dimensional motion

(i) with constant speed must have zero acceleration.

(ii) with positive value of acceleration must be speeding up.

39. Distinguish between speed and velocity.

40. State whether the motion is one, two or three dimensional in the following cases:

(i) a kite flying on a windy day,

(ii) a speeding car on a long straight high way,

(iii) motion of a planet around the sun?