XI UT1 Objective 2024-25.pdf

DAV Public School Ghumarwin UT-1 ( Objective Paper) (2024-25) Subject- Physics Class XI Timing: 30 min...

DAV Public School Ghumarwin UT-1 ( Objective Paper) (2024-25) Subject- Physics Class XI Timing: 30 min MM.-20 General Instructions: 1. There are a total of 20 questions.Each question carries one mark. 2. Attempt all questions. 3. There is no negative marking. 4. Section A contains MCQs from question number 1 to question number 15 5. section B contains assertion reason questions from question number 16 to question number 20. Section- A (MCQs) 1. Amongst the following options, which is a unit of time? (a) Light year (b) Parsec (c) Year (d) None of these 2. Which among the following is the Supplementary Unit——– (a)Mass (b) Time (c) Solid angle (d) Luminous Intensity 3. The smallest value which is measured using an instrument is known as ________ (a)Absolute count (b) Least count (c) Round off value (d) Minimum count 4. The dimensions of kinetic energy is (a) [M 2L2T]. (b) [ML2T]. (c) [ML 2T-2] (d) [ML 2T-1] 5. A force F is given by F = at + bt², where t is time. What are the dimensions of a and b? (a) MLT-1 and MLT0. (b) MLT-3 and ML2T4. (c) MLT-4 and MLT1. (d) MLT-3 and MLT-4 6. Which of the following numerical values has three significant figures? (a) 5.055 (b) 0.050 (c) 50.50 (d) 0.500 7. The respective number of significant figures for the numbers 23.023, 0.0003 and 2.1×10-3 are (a) 5, 1, 2 (b) 5, 1, 5. (c) 5, 5, 2 b(d) 4, 4, 2 8. The numerical ratio of displacement to distance for a moving object is (a) always less than 1 (b) always equal to 1 (c) always more than 1 (d) equal to or less than 1 9. Area under velocity-time curve over a given interval of time represents (a) acceleration. (b) momentum. (c) velocity. (d) displacement 10. A body starts from rest and travels for t seconds with uniform acceleration of 2 m/s². If the displacement made by it is 16 m, the time of travel t is (a) 4 s. (b) 3 s. (c) 6 s. (d) 8 s 11. A boy moves on a circular distance of radius R. Starting from a point A he moves to a point B which is on the other end of the diameter AB. The ratio of the distance travelled to the displacement made by him is (a) π/2. (b) π. (c) 2π. (d) 4π 12. If Position of a particle is given by x = (4t2 – 8t), then which of the following is true? (a) Acceleration is zero at t = 0 (b) Velocity is zero at t = 0 (c) Velocity is zero at t = 1s (d) Velocity and acceleration will never be zero 13. A boy starts from a point A, travels to a point B at a distance of 3 km from A and returns to A. If he takes two hours to do so, his speed is (a) 3 km/h (b) zero (c) 2 km/h (d) 1.5 km/h 14.Which one of the following is the unit of velocity? (a) kilogram. (b) metre. (c) m/s. (d) second 15. Consider a body moving with an acceleration of 2 m/s². After t seconds its velocity is 10 m/s. Find ‘t’. (a)4 s. (b)20 s. (c)5 s. (d)8 s Section- B ( Assertion- Reason questions) These questions consist of two statements, each printed as Assertion and Reason. While answering these questions, you are required to choose any one of the following four responses. (a) If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion. (b) If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion. (c) If the Assertion is correct but Reason is incorrect. (d) If both the Assertion and Reason are incorrect. Q16. Assertion : Dimensional constants are the quantities whose values are constant. Reason : Dimensional constants are dimensionless. Q17. Assertion: ‘Light year’ and ‘Wavelength’ both measure distance. Reason : Both have dimensions of time. Q18. Assertion : Parallax method cannot be used for measuring distances of stars more than 100 light years away. Reason : Because parallax angle reduces so much that it cannot be measured accurately. Q19. Assertion : Position-time graph of a stationary object is a straight line parallel to the time axis. Reason : For a stationary object, position does not change with time. Q20. Assertion : The average and instantaneous velocities have the same value in a uniform motion. Reason : In uniform motion, the velocity of an object increases uniformly.