Student Name Roll. No Subject Test Total Marks Physics Chapter 4 60 Obtained Mark’s Class 9th Instructions: • • • Cutting and overwriting will be the cause of the deduction of marks. Cheating is not allowed at any cost. Try to read every question carefully and then attempt them. (Objective Type) Time Allowed: 15 minutes Q1. Tick the correct option from A, B, C and D. 1×12=12 1. The number of forces that can be added by head to tail rule are: a) 2 b) 3 c) 4 d) Any number 2. A force of 10 N is making an angle of 30° with the horizontal. Its horizontal component will be: a) 4N b) 5N c) 7N d) 8.7N 3. Two equal but unlike parallel forces having a different line of action produce: a) A torque b) A couple c) Equilibrium d) Neutral equilibrium 4. If F=4N, F, = 3N what is magnitude of resultant force: a) 7N b) 5N c) 12N d) 10N b) Nm c) Ns-1 d) Nm-1 5. SI unit of Torque is: a) Ns 6. If force b 200 N and length of spanner is 0.15 m then torque will be: a) 15 Nm b) 30 Nm c) 10 Nm d) 20Nm 7. According to the second condition of equilibrium must be zero: a) Angular Acceleration b) Linear Acceleration c) Rotational Force d) Sum of Torque 8. A force of 10 N is making an angle of 30° with the horizontal. Its horizontal component will be: a) 4N b) 5N c) 7N d) 8.7N Mr. Imtiaz Tariq Imtiaztariq096@gmail.com 0334-717189 9. The Moment Arm is represented by a sign: a) T b) L c) F d) N c) Work d) Distance c) 0.5 d) 0.577 10. Rate of change of momentum is equal to: a) Force b) Torque 11. The value of Sin 60° is equal to: a) 0.866 b) 0.707 1. The number of perpendicular components of a force is a) 1 Mr. Imtiaz Tariq b) 2 c) 3 Imtiaztariq096@gmail.com d) 4 0334-717189 Name Roll Number Paper Type Time Allowed Subjective 1:45 Hours Obtained Marks Total Marks 48 Q2. Write short answers to any FIVE (5) question: 5×2=10 i. When is a body said to be in equilibrium? ii. What is the second condition for equilibrium? iii. How head to tail rule helps to find the resultant of forces iv. What is the resultant force? v. Find the vertical component of a force of 5ON making an angle of 30° with the x-axis. vi. What is meant by a rigid body? vii. A mechanic tightens the nut of a bicycle using a 15 cm long spanner by exerting a viii. force of 20ON. Find the torque that has tightened it. ix. Define torque and write its formula. Q3. Write short answers to any FIVE (5) question: 5×2=10 i. Define axis of rotation. ii. Differentiate between moment arm and line of action of a force. iii. In a right-angled triangle length of the base is 4cm and its perpendicular is 3cm then find the length of its hypotenuse. iv. What is meant by plumb line? v. Define parallel forces. Write the names of its types. vi. Write the mathematical forms of conditions of torque. vii. State the principle of moments. viii. Define head to tail rule. Q4. Write short answers to any FIVE (5) question: 5×2=10 i. Define perpendicular ii. Describe the line of action of a force. iii. What is the resolution of force? iv. Think of a body that is at rest but not in equilibrium v. Differentiate between clockwise moment and anti-clockwise moment. vi. Define Like Parallel forces and moment arm. vii. What are First Condition and Second Condition for equilibrium? viii. Define torque and moment arm. Mr. Imtiaz Tariq Imtiaztariq096@gmail.com 0334-717189 (Part-II) Note: Attempt any Two questions. Q5. . a. Define torque or moment of force. Explain on what factors, does it depend? b. The steering of a car has a radius of 16 cm. Find the torque produced by a couple of 50ON. Q6. a. State and explain the first condition for equilibrium. b. Find the magnitude and direction of a force, its x-component is 12 N and y-component is 5N. Q7. a. b. 9×2=18 Define resolution of force. How can a force be resolved into its perpendicular components? Find the perpendicular components of a force of 50 N making an angle of S with an x-axis. Mr. Imtiaz Tariq Imtiaztariq096@gmail.com 0334-717189