A and a mass are connected by a light string over a light frictionless pulley fixed to the ceiling of a lift that accelerates upward at . Taking , what force does the string exert on the pulley's support (the ceiling)?
Answer and explanation
Correct answer: C. 57.6 N
- Step 1: In an upward accelerating reference frame of acceleration , the effective gravitational acceleration is .
- Step 2: Calculate the tension in the string connecting masses and : .
- Step 3: The string passes over the pulley and pulls downward on both sides, exerting a total downward force on the pulley axle support of .
Answer
57.6 N.
Why not the others: accounts for only one branch of the string, and assumes the lift is stationary.
Practise more Laws of motion.
Free questions with an explanation for every one, and full timed JEE Main mock tests.
More Laws of motion questions
- What is the momentum (in kg m/s) of a object moving at ?
- What is the momentum (in kg m/s) of a object moving at ?
- What is the momentum (in kg m/s) of a object moving at ?
- What is the momentum (in kg m/s) of a object moving at ?
- What is the momentum (in kg m/s) of a object moving at ?
- What net force (in N) gives a mass an acceleration of ?