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Questions in physics

[Done] Select the correct answer. What is the value of work done on an object when a $0.1 \times 10^2$-newton force moves it 30 meters and the angle between the force and the displacement is $25^{\circ}$? A. $2.7 \times 10^2$ joules B. $3.0 \times 10^2$ joules C. $7.5 \times 10^2$ joules D. 0 joules

[Done] III ASSERTION AND REASON: 10. Assertion (A): A clock shows periodic motion. Reason (R): The hands of a clock move back and forth. a) Both A and R are true, and R is the correct explanation of A. b) Both A and R are true, but R is not the correct explanation of A. c) A is true but R is false. d) A is false but R is true. 11. Assertion (A): A ceiling fan in motion shows circular motion. Reason (R): Circular motion occurs when an object moves in a straight line. a) Both A and R are true, and R is the correct explanation of A. b) Both A and R are true, but R is not the correct explanation of A. c) A is true but R is false. d) A is false but R is true. IV ANSWER THE FOLLOWING QUESTIONS: 12. Imagine you're an engineer. You must design a robot that can walk straight, turn in a circle, and swing its arms. What types of motion would be involved in each part? 13. Fill in the correct scientific word related to motion and measurement. (a) I am the SI unit of length. (5 letters) (b) I swing to and fro. (8 letters) 14. Can an object be in motion with respect to one thing and at rest with respect to another? Explain with an example. CASE STUDY: Ravi and his family went on a road trip from Chennai to Bangalore, covering a distance of 350 kilometers. They started at 6:00 AM and reached by 12:00 PM, with two breaks of 30 minutes each for breakfast and fuel. Ravi was curious about the trip and noted the time, speed, and motion of different vehicles they saw on the highway. He saw trucks moving slowly, cars at high speeds, and also bicycles in nearby towns. He also noticed how the wheels of the car moved in circular motion, while the car itself moved in rectilinear motion along the highway. 15. What type of motion was shown by the car moving along the straight highway? a) Circular motion b) Rectilinear motion c) Oscillatory motion d) Random motion 16. How long did Ravi's journey take, excluding the breaks? a) 6 hours b) 5 hours c) 5.5 hours d) 6.5 hours 17. Which of the following objects showed circular motion in the case? a) The steering wheel b) The entire car c) Trees by the road d) Speedometer needle 18. Calculate the average speed of the car during the journey (excluding break time). Hint: Speed = Distance / Time

[Done] Electrical conductivity is the ability of metals to conduct heat and electricity. Match the items in Column A with their correct functions or descriptions in Column B: | Column A | Column B | |--------------------|-------------------------------| | 1. Knife | A. reflects the existing light | | 2. Wood | B. cooking foods | | 3. Cloth | C. conducts electricity | | 4. Metal pot | D. removes dirt/soiled clothes | | 5. Ceramic acid | E. cleans the toilet bowl | | 6. Muriatic acid | F. hold hot liquid | | 7. Powder detergent| G. food preparation or cutlery| | 8. Mirror | H. chairs and tables | | 9. Bath soap | I. Blanket | | 10. Electrical wires| J. Personal hygiene |

[Done] What will most likely happen if a sound wave moves from the air through a solid? A. It will increase in frequency. B. It will decrease in speed. C. It will increase in speed. D. It will decrease in wavelength.

[Done] What is the acceleration of an object if a force of 30 N is applied to a 6 kg object? A. $3 m / s ^2$ B. $10 m / s ^2$ C. $5 m / s ^2$ D. $15 m / s ^2$

[Done] An electric device delivers a current of [tex]$15.0 A$[/tex] for 30 seconds. How many electrons flow through it?

[Done] 78. What is the magnitude of the electric field at a field point 2.0 m from a point charge q = 4.0 nC? (a) 18.0 N/C (b) 9.0 N/C (c) 36.0 N/C (d) 6.0 N/C

[Done] What is a semiconductor? Definition of the following: Semiconductor Conductor Insulator Energy band

[Done] Select the best answer for the question. 13. In which of the following units is acceleration expressed? A. Kilograms B. Newtons C. Meters per second squared D. Foot-pounds

[Done] You burn a log on a fire. You use the fire to warm yourself and to light up the room to read a book. Which energy transformation is taking place? A. Chemical energy is transformed to nuclear energy and thermal energy. B. Thermal energy is transformed to light energy and chemical energy. C. Chemical energy is transformed to light energy and thermal energy. D. Nuclear energy is transformed to potential energy and thermal energy.