Q. A cyclist is moving at 15 m/s and a pedestrian is walking at 5 m/s in the same direction. What is the speed of the cyclist relative to the pedestrian?
A.
10 m/s
B.
15 m/s
C.
5 m/s
D.
20 m/s
Solution
Relative speed = Speed of cyclist - Speed of pedestrian = 15 m/s - 5 m/s = 10 m/s.
Q. A cyclist is moving at 15 m/s and passes a stationary observer. If the observer starts moving at 5 m/s in the same direction, what is the speed of the cyclist relative to the observer?
A.
10 m/s
B.
15 m/s
C.
20 m/s
D.
5 m/s
Solution
Relative speed = Speed of cyclist - Speed of observer = 15 m/s - 5 m/s = 10 m/s.
Q. A cyclist is moving at 15 m/s towards the east while a car is moving at 25 m/s towards the west. What is the relative speed of the cyclist with respect to the car?
A.
10 m/s
B.
15 m/s
C.
40 m/s
D.
25 m/s
Solution
Relative speed = Speed of cyclist + Speed of car = 15 m/s + 25 m/s = 40 m/s.
Q. A cyclist is moving at a speed of 15 km/h. If a car is moving in the same direction at 30 km/h, what is the relative speed of the car with respect to the cyclist?
A.
15 km/h
B.
30 km/h
C.
45 km/h
D.
0 km/h
Solution
Relative speed = speed of car - speed of cyclist = 30 - 15 = 15 km/h.
Q. A person is running at 3 m/s on a moving escalator that moves at 2 m/s in the same direction. What is the speed of the person relative to a stationary observer?
A.
1 m/s
B.
3 m/s
C.
5 m/s
D.
2 m/s
Solution
Speed of person relative to observer = Speed of escalator + Speed of person = 2 m/s + 3 m/s = 5 m/s.
Q. A person is running at a speed of 10 m/s. If he is running towards a train moving at 20 m/s in the opposite direction, what is the relative speed of the train with respect to the person?
A.
10 m/s
B.
20 m/s
C.
30 m/s
D.
40 m/s
Solution
Relative speed = speed of train + speed of person = 20 + 10 = 30 m/s.
Q. A person walks at 4 km/h in still water. If the current of the river is 2 km/h, what is the speed of the person relative to the bank when walking upstream?
A.
2 km/h
B.
4 km/h
C.
6 km/h
D.
8 km/h
Solution
Speed upstream = Speed of person - Speed of current = 4 km/h - 2 km/h = 2 km/h.
Q. A swimmer can swim at 4 km/h in still water. If he swims across a river that is 1 km wide and the current is 2 km/h, how long will it take him to reach the opposite bank?
A.
15 minutes
B.
30 minutes
C.
45 minutes
D.
1 hour
Solution
Time = distance/speed = 1 km / 4 km/h = 0.25 hours = 15 minutes.
Understanding "Relative Motion" is crucial for students preparing for school and competitive exams in India. This topic not only forms the basis of many physics concepts but also frequently appears in various examination formats. Practicing MCQs and objective questions on relative motion can significantly enhance your exam preparation, helping you identify important questions and improve your scoring potential.
What You Will Practise Here
Concept of relative velocity and its significance
Understanding frames of reference and their applications
Relative motion in one and two dimensions
Key formulas related to relative motion
Graphical representation of relative motion
Common scenarios involving moving objects
Problem-solving techniques for relative motion questions
Exam Relevance
The topic of relative motion is a staple in CBSE, State Boards, NEET, and JEE exams. Students can expect questions that assess their understanding of relative velocity, the application of formulas, and the ability to analyze motion from different frames of reference. Common question patterns include numerical problems, conceptual questions, and application-based scenarios, making it essential to master this topic for a solid performance in exams.
Common Mistakes Students Make
Confusing the concepts of absolute and relative velocity
Misinterpreting the direction of motion in different frames
Neglecting to apply the correct formulas in problem-solving
Overlooking the significance of diagrams in understanding motion
Failing to account for the effects of acceleration in relative motion problems
FAQs
Question: What is relative motion? Answer: Relative motion refers to the calculation of the motion of an object as observed from a particular frame of reference, which can differ based on the observer's own motion.
Question: How do I solve relative motion problems effectively? Answer: To solve relative motion problems, identify the frames of reference, apply the relevant formulas, and carefully analyze the direction of each object's motion.
Now that you have a clear understanding of relative motion, it's time to put your knowledge to the test! Solve practice MCQs and objective questions to reinforce your understanding and boost your confidence for the upcoming exams. Remember, consistent practice is the key to success!
Soulshift Feedback×
On a scale of 0–10, how likely are you to recommend
The Soulshift Academy?
