Which of the following is a fundamental unit in the SI system?
A) Newton
B) Joule
C) Kilogram
D) Watt
Answer: C) Kilogram
Explanation: The kilogram is one of the seven fundamental units in the SI system, representing mass. Newton, Joule, and Watt are derived units.
Question 2 (2019, Q7):
Which of the following is a vector quantity?
A) Speed
B) Distance
C) Velocity
D) Temperature
Answer: C) Velocity
Explanation: Velocity is a vector quantity because it has both magnitude and direction. Speed, distance, and temperature are scalar quantities.
Question 3 (2020, Q15):
A car accelerates uniformly from rest at 2 m/s² for 5 seconds. What is its final velocity?
A) 2 m/s
B) 5 m/s
C) 10 m/s
D) 20 m/s
Answer: C) 10 m/s
Explanation: Using the formula \( v = u + at \), where \( u = 0 \), \( a = 2 \, \text{m/s}² \), and \( t = 5 \, \text{s} \), the final velocity \( v = 0 + (2 \times 5) = 10 \, \text{m/s} \).
Question 4 (2018, Q23):
The acceleration due to gravity on the moon is about 1.6 m/s². What is the weight of a 10 kg object on the moon?
A) 1.6 N
B) 16 N
C) 10 N
D) 100 N
Answer: B) 16 N
Explanation: Weight = mass × acceleration due to gravity. On the moon, \( W = 10 \, \text{kg} \times 1.6 \, \text{m/s}² = 16 \, \text{N} \).
Question 5 (2022, Q9):
Two forces of 5 N and 12 N act at right angles to each other. What is the magnitude of the resultant force?
A) 7 N
B) 13 N
C) 17 N
D) 25 N
Answer: B) 13 N
Explanation: The resultant force is calculated using the Pythagorean theorem: \( R = \sqrt{5² + 12²} = \sqrt{25 + 144} = \sqrt{169} = 13 \, \text{N} \).
Question 6 (2020, Q18):
A force of 10 N moves an object 5 m in the direction of the force. What is the work done?