13)Plz anyone explain the meaning of pseudo force.I couldn't understand what actually it means.
(1) A monkey of mass 15kg is climbing on a rope with one end fixed to the ceiling.If it wishes to go up with an acceleration of 1m/s2,how much force should it apply to the rope?If the rope is 5m long and the monkey starts from rest,how much time will it take to reach the ceiling?
(2) A block A can slide on a frictionless incline of angle x & length l,kept inside an elevator going up with uniform velocity v.Find the time taken by the block to slide down the l dist. If it is released from the the top of the incline.
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8 Answers
111) it tension in the rope be T, then
T - 15g = 15.1
or T=165N
hence the monkey should apply 165N in the downward dirn
2) as the elevator moves with const vel., the frame will be inertial.... so simply writing newton's law,
l = (1/2)(gsinx).t2
11m = 15 kg of monkey. a = 1 m/s2.
T - ( mg + ma) = 0
T – [15g + 15(1)] = 0
T = 15 (10 + 1) T = 15 × 11
T = 165 N.
The monkey should apply 165N force to the rope.
Initial velocity u = 0 ; acceleration a = 1m/s2 ; s = 5m.
s = ut + ½ at2
5 = 0 + (1/2)1 t2
t2 = 5 × 2
t = √10 sec.
Time required is √10 sec.
Please draw the fbd yourself, if you cant then ping me
11The physically apparent but nonexistent force needed by an observer in a noninertial frame to make Newton's laws of motion hold true. The centrifugal force is a pseudo force. Also called fictitious force.
A fictitious force, also called a pseudo force, d'Alembert force or inertial force, is an apparent force that acts on all masses in a non-inertial frame of reference, such as a rotating reference frame. The forces may be treated algebraically like a real force, but the fictitious forces do not necessarily obey Newton's first law.
The force F does not arise from any physical interaction but rather from the acceleration a of the non-inertial reference frame itself. As stated by Iro: "Such an additional force due to nonuniform relative motion of two reference frames is called a pseudo-force."
http://www.answers.com/topic/fictitious-force
21take a book,put a pen on it...now apply some force on the book to produce acceleration..u will see that the pen is moving in the opposite direction WITH RESPECT TO THE BOOK.. [u may think this is because of inertia..but its nt inertia as it is not an inertial reference frame( it is accelerated) n u cant apply newtons law directly here]... so there must be a force which is pushing the pen in opposite direction..the force acting on the pen is nothing but PSEUDO FORCE....
the magnitude of the pseudo force acting on the pen is = mass of the pen* acceleration u gave to the book
if u push the book with uniform velocity u will see that the pen is in rest WITH RESPECT TO THE BOOK,because this is an inertial reference frame...so there is no pseudo force acting on the pen.
u will also see that if u provide smaller acceleration to the book,the pen is in rest W R T BOOK.. that is because here the frictional force between the book and pen ≥ the pseudo force......
hope i explained well :P:P
6well its wrong to think that pseudo force is an additional force........
its just a component of the net force arising in non inertial frames so that newton's laws can be applied in that frame as well.
1well take in the best and i think simplest way
it's just a kind of correctional force that is applied in a non-inertial rame so that newton's continue to hold in that frame