General Knowledge - Physics - Discussion
Discussion Forum : Physics - Section 1 (Q.No. 57)
57.
On a stationary sail boat, air is blown from a fan attached to the boat. The boat
Discussion:
59 comments Page 5 of 6.
Archit singhal said:
1 decade ago
I can't understand the reason of no moving. Because hovercraft is a device which has a fan mounted on it and it can move in every surface. So why is it not?
Aravind said:
1 decade ago
When the fan pushes the sail by blowing air, the air also pushes the fan in opposite direction. As the fan is a part of the boat, the vector sum of the momenta of the fan and the boat is zero. The boat will only move if some external agency applies force on it.
Prakash said:
1 decade ago
All dear buddies the boat does not move because the air is blown from the Fan not to the Fan So it doesn't receive any thrust or force hence it does not move.
Alia said:
1 decade ago
Answer is B because by newton's third law of motion every action has opposite & equal reaction but here the boat will not move because the force is not sufficient to make the boat to move & for newton's third law mass must be equal to form equal reaction.
KARTIKEYA said:
1 decade ago
If the boat does not moves then I can also give a reason that car will not move because engine is mounted to it.
The fan is capable of producing enough thrust to move the boat.
I disagree with @Banshi dhar and @Ajay.
The fan is capable of producing enough thrust to move the boat.
I disagree with @Banshi dhar and @Ajay.
Srijoni said:
1 decade ago
Why the boat does not move?
Prasuna said:
1 decade ago
If there is sufficient force definitely boat will move.
Aiswarya said:
1 decade ago
Please tell me what is the reason for it.
Dhasaradan said:
1 decade ago
Question is totally unclear to describe. The required information is whether the fan is mounted where. Whether it will produce thrust to move a boat. If it is mounted on the boat which can not create any impact on stability of the boat then boat will at least have movement up and down which is not an option given here.
Priyansh said:
1 decade ago
The boat will move because of the reaction provided by the air (in the opposite direction).
This is the similar case as the jet engine, air is of certain momentum is sucked and by combustion of fuel its momentum increases so the net force on the jet will be equals to the rate of change of momentum.
This is the similar case as the jet engine, air is of certain momentum is sucked and by combustion of fuel its momentum increases so the net force on the jet will be equals to the rate of change of momentum.
Post your comments here:
Quick links
Quantitative Aptitude
Verbal (English)
Reasoning
Programming
Interview
Placement Papers