A mass of 1 kg is suspended by a thread. It is(i) lifted up with an acceleration of 4.9 ms-2(ii) lowered down with an acceleration of 4.9 ms-2The ratio of tensions in the thread is:
Correct answer: A. 3 : 1
- A. 3 : 1
- B. 1 : 3
- C. 1 : 2
- D. 2 : 1
Explanation
This is the following solution: (i) When lifted up with an acceleration of 4.9 m/s2: Tension = Weight + Force due to acceleration T1 = (1 kg) (9.8 m/s2) + (1 kg) (4.9 m/s2) T1 = 9.8 N + 4.9 N = 14.7 N (ii) When lowered down with an acceleration of 4.9 m/s2: Tension = Weight - Force due to acceleration T2 = (1 kg) (9.8 m/s2) - (1 kg) (4.9 m/s2) T2 = 9.8 N - 4.9 N = 4.9 N The ratio of T1 to T2 is: T1 / T2 = (14.7 N) / (4.9 N) = 3 So, the ratio of tensions in the thread is 3 in both cases.
Report an error
The more specific you are, the faster it gets fixed. A source beats an opinion.
Prefer email? [email protected]
About Force and Motion
Displacement, velocity and acceleration describe motion, including the horizontal and vertical components of projectile motion. The chapter connects these quantities with Newton's laws, momentum and impulse, then applies conservation of momentum to collisions, distinguishing elastic collisions from inelastic ones.
Practise Force and Motion
1,416 free Force and Motion MCQs from Physics, each with the correct answer and an explanation. Unlimited attempts, no account needed.
Discussion
Stuck on an option, or know a faster way to get there? Ask or explain it here.
No comments yet. Be the first to explain this one.
Exams that ask Physics questions like this
Physics is on 16 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.
More Force and Motion questions
A body moving with velocity v can be stopped by a force F in direction of it. Same body moving with velocity 5v can be stopped by a force 5F in distance equal to:
Two bodies 'x' and 'Y' are attached to the ends of a string which passes over a pulley so that the two bodies hang vertically. If the mass of the body 'x' is 5 kg and that of body 'Y' is 4.8 kg. Find the acceleration?(g = 9.8 m/s^2)
An object moves 20 m towards the east and then 10m towards the west in 5 seconds. What is its average velocity and average speed?
Which of the following is an example of an inelastic collision?
A car starts from rest and moves with a constant acceleration. During the 5th second of its motion, it covers a distance of 36 meters. What is the acceleration of the car?
A ball of mass 2 kg travelling at 8 ms-1 strikes a ball of mass 4kg travelling at 2ms-1. Both balls are moving along the same straight line as shown. After collision, both balls move at the same velocity v. What is the magnitude of the velocity V?