Circular Motion, Angular Variables, Angular Velocity, Angular Acceleration, Application of Newton’s Laws of Motion.
So, in order to prepare for the ECAT Entry Test, you must know the concepts of Physics Circular Motion thoroughly. This section is dedicated to important/multiple choice questions (MCQs) based on Circular Motion, Angular Variables, Angular Velocity, Angular Acceleration, and Newton’s Laws of Motion, aiding students to polish their knowledge and sharpening their problem-solving abilities.
Understanding Physics Circular Motion
The motion of an object moving along a circular path is called Physics Circular motion. The motion in a circular path is influenced by the angular displacement, angular velocity, and angular acceleration parameters. This is directly why objects moving in a circular motion experience centripetal force. It is essential to understanding how things work in real life, eg planetary motion, vehicle turns, and artificial satellites.
Angular Variables and Their Importance
In circular motion, angular variables play a significant role in describing how an object rotates. The key angular variables include:
- Angular Displacement (θ): It is the angle by which an object moves on a circular path. It is usually measured in radians.
- Angular Velocity (ω): The change in angular displacement per unit of time, measured in radians/second.
- Angular Acceleration (α): How fast is the angular velocity changing, that is how quickly the object spins up or spins down.
Hence, for ECAT Entry Test preparation, these variables become essential, as they key up the way towards understanding rotational kinematics and dynamics.
Entry Test Physics Circular Motion MCQS Online Preparation Sample Paper 1 Questions with Answer
1. When a body moves in a circle in the clockwise direction the angular displacement ∆Ѳ is taken as?
- Positive
- Negative correct
- Both ways
- None of these
2. S.I. unit of angular velocity is
- Degree per second
- Revolution per minute
- Radian per second correct
- None of these
3. The rate at a which the angular displacement is changing with time is called?
- Average angular velocity
- Angular acceleration
- None of these
- Angular velocity correct
4. As the ∆t approaches to zero, the limit of ratio ∆ω/∆t becomes
- Variable angular acceleration
- Instantaneous angular acceleration instantaneous correct
- None of these
- Average acceleration
5. Angular displacement is a vector quantity for?
- All values of ∆Ѳ
- Very small value of ∆Ѳ correct
- None of these
- Small value of ∆Ѳ
6. One radian is equal to
- 58⁰
- 57.3⁰ correct
- 57⁰
- 360⁰/π
7. The S.I. unit of angular displacement is
- Degrees
- Revolution
- Radian correct
- All of these
8. I revolution is equal to
- None of these
- 2π radian
- 360⁰
- Both correct
9. ‘S’ is the are length and after one revolution it becomes
- 2πr correct
- 2 π
- None of these
- 2π/r
- 10. Angular displacement generally expressed in
- Revolution
- Degrees
- Radian
- All of these correct
11. The rate of change of angular velocity is called
- Angular displacement
- Angular acceleration correct
- Instantaneous velocity
- None of these
12. Angle subtended at the center of the circle by a body is called?
- All of these
- Linear velocity
- Angular velocity
- Angular displacement correct
13. 2π radian is equal to the degrees
- None of these
- 360⁰ correct
- 90⁰
- 180⁰
14. Radian is the unit of angular displacement which is?
- Greater than degree correct
- None of these
- Equal
- Less than degree
15. The direction of angular acceleration is
- Opposite to the axis of rotation
- Along the axis of rotation correct
- Perpendicular to the axis of rotation
- None of these
16. When a body moves in a circle in the counter clockwise direction the angular displacement ∆Ѳ is taken as?
- None of these
- Negative
- Both ways
- Positive correct
17. The direction of angular displacement is determined by using
- None of these
- Head-to-tail rule
- Right angle rule correct
- Fleming left hand rule
18. Angular velocity is a
- Scalar quantity
- Constant quantity
- None of these
- Vector quantity correct
19. What is the relation between an are length and the angle Ѳ (in radian) with the ‘r’ as its radius
- S = r Ѳ correct
- None of these
- Ѳ = r/S
- R = Ѳ/S
20. Angular acceleration is a
- Scalar quantity
- Vector quantity correct
- Variable quantity
- None of these
Entry Test Physics Circular Motion MCQS Online Preparation Sample Paper 2 Questions with Answer
- 1. The rotational analogue of Newton’s second law of motion is
- None of these
- mrα²
- mr²α correct
- mrα
2. The relation between linear acceleration and angular acceleration is
- a=ωr/α
- a = rωα
- a=r/ω α
- at=rα correct
3. The law of conservation is important in many sport like
- Diving
- All of these correct
- Ice-skating
- Gymnastics
4. The axis of ration of an object will not change its orientation unless
- None of these
- Internal torque acts in one direction
- Internal torque acts
- External torque acts correct
5. The linear velocity in a circle is called
- Linear velocity
- None of these
- Angular velocity
- Tangential velocity correct
6. An electric fan rotating in 3 revs¯¹ is switched off. It come sot rest in 18.0 sec. Find the value of acceleration which is
- 0027 revs¯²
- – 0.167 revs¯² correct
- + 1.267 revs¯²
- – 0.152 revs¯²
7. The force required to bend the normally straight path of the particle into circular path is called
- Centripetal force correct
- Normal force
- Applied force
- Reactional force
8. The Earth’s axis of rotation is
- Not fixed
- Remains fixed in one direction correct
- None of these
- Remains fixed
9. The equations of angular motion only hold true when the axis of rotation is
- Fixed in some equations
- Not fixed
- None of these
- Fixed correct
10. The moment of inertia plays the same role in angular motion as in linear motion as
- Density
- Mass correct
- None of these
- Weight
11. The units of angular acceleration is
- None of these
- Radian per second
- Radian
- Radian per minute correct
12. In the relations ∆S/∆t =r ∆Ѳ/∆t. If he limit is taken as ∆t → 0 then relation takes the form
- v = r/ω
- V = rω correct
- a = rV
- a = rω
13. On the circumference of a circle, the magnitude V is very small and has direction
- Perpendicular to the point
- None of these
- Changes from time to time
- Along he tangent to the circle correct
14. In a uniform circular motion of a particle, the direction changes but not its
- B and C correct
- Angular displacement
- Force towards center
- Magnitude of velocity
15. All points on a rigid body rotating about a fixed axis have
- Same angular acceleration
- Don’t have angular speed correct
- None of these
- Same angular displacement
16. A 10 kg car is turning around a corner at 10ms¯¹. The radius of the circular are is 10m. Find the force between the types and pavement which is
- 1.0 x 10⁴ N correct
- 1.0 x 10⁶ N
- 1.0 x 10² N
- None of these
17. In the relation ∆S/∆t = r ∆Ѳ/∆t. If the limit is taken as ∆t → 0 time ∆S/∆t represents
- Linear velocity correct
- Angular velocity
- Linear acceleration
- None of these
18. By the use of angular variable we can describe the
- Angular motion of a body correct
- None of these
- Linear motion of body
- Both
19. The centripetal force in terms of its angular measure is given by
- Fc = mrω² correct
- Fc = mr²ω
- None of these
- Fc = mr²ω²
20. The quantity mr² is known as
- Moment arm
- Moment of inertia correct
- None of these
- Moment of force
Entry Test Physics Circular Motion MCQS Online Preparation Sample Paper 3 Questions with Answer
1. If the particle is moving in a circle of radius ‘r’ with uniform angular velocity ω. The angle between r and tangential velocity is
- 0⁰
- 180⁰
- 270⁰
- 90⁰ correct
2. For an elliptic orbit, the satellite has speed of
- None of these
- 35,000 Kmh¯¹
- 37,000 Kmh¯¹
- 30,0000 Kmh¯¹ correct
3. Moment of inertia of a thin ring or hoop is
- 2/3 mr²
- 1/3 mr²
- Mr² correct
- 5/6 mr²
4. Moment of inertia of a solid disc or cylinder is
- ½ mr² correct
- mr²
- ¼ mr²
- 1/3 mr²
5. Moment of inertia of thin rod is
- 1/15mL²
- 1/2mL²
- 1/12mL² correct
- 1/6mL²
6. The angular momentum is a vector quantity with due
- Perpendicular to the axis of rotation
- Along the axis of rotation correct
- At the axis of rotation
- None of these
7. The law of conservation of momentum says that the total angular momentum of the system remains constant if no external
- None of these
- Frictional force action it
- Torque acts on it correct
- Force acts on it
8. The angular momentum of a particle is given as
- L = p x V
- None of these
- L = m x p
- L = r x p correct
9. Law of conservation of momentum has been verified for the
- A and C correct
- Submicroscopic level
- Cosmological level
- Microscopic level
10. Moment of inertia of a sphere is
- 2/5 mr² correct
- 1/3 mr²
- 4/5 mr²
- ¾ mr²
11. For a circular orbit, the satellite has speed of
- 26,000 Kmh¯¹
- 20,00 Kmh¯¹
- 25,000 Kmh¯¹
- 27,000 Kmh¯¹ correct
12. The orbital radius as the revolving body is revolving is
- Smaller
- Very Smaller
- Larger correct
- None of these
13. The spin angular momentum is the angular momentum of a
- Rotating body
- None of these
- Revolving body
- Spiming boy correct
14. Moment of inertia depends on mass and also on
- r³
- r
- r² correct
- None of these
15. SI unit of angular momentum is
- Kgms¯¹
- Kgm³s¯¹
- Kgm²s¯²
- Kgm²s¯¹ correct
16. A disc roll down a hill of 10.0 m from rest without slipping. What is its speed at the bottom
- 11.3 ms¯¹
- 11.4 ms¯¹ correct
- 10.2ms¯¹
- None of these
17. Satellites are objects that orbit around the
- Planet
- Sun
- All of these
- Earth correct
18. Satellites are held in orbits by gravitational pull by Earth and are putt into orbit by
- None of these
- Initial velocity
- Escape velocity
- Rockets correct
19. The mass distribution of a rigid body is
- Not uniform correct
- Both
- None of these
- Uniform
20. The orbital angular momentum is associated with the motion of a body
- Along a circular path correct
- None of these
- Rotating body
- Revolving body
Application of Newton’s Laws in Circular Motion
Newton’s Laws of Motion apply to circular motion just as they do to linear motion:
- First Law: A body in uniform circular motion remains in motion unless acted upon by an external force.
- Second Law: The force required to keep an object moving in a circular path is given by F = mω²r.
- Third Law: For every force exerted, there is an equal and opposite reaction force, which is seen in the balance between centripetal and centrifugal forces.
Conclusion
Practice Physics Circular Motion with its angular parameters for the best results in the ECAT Entry Test. This ensures that when students prepare for complex MCQs, they learn the basics such as angular displacement, angular velocity, angular acceleration, and Newton’s laws, which they can build upon later on. Concentrate on these concepts, solve more questions, and ace your preparation for ECAT!