BT prac FST 1

2) In forced oscillation of a particle, the amplitude is maximum for a frequency w1 of the force, while the energy is maximum for a frequency w2 of the force, then

(A) w1 = w2

(B) w1 < w2

(C) w2 < w1 when damping is small and w2 > w1 when damping is small

(D) w2 > w1

Ans (A)

Q1) no relation b/w t and t₀ ?

3) A space lab is revolving round the earth at a height 3R from earth's surface where R is radius of the earth. The time-period of a seconds pendulum in this lab is

Option
zero
infinity
2 sec
9.8 sec

Ans is infinity

4) As atomic number A of nucleus increa-ses,

the 'binding energy per nucleon' (B) increases when neutron-proton ratio' increases
initially the ratio n/p is unity
initially n/p increases and later decreases
initially B decreases and then increases

Ans B

MATHS

Regression equation of Y on X is 3x + 4y - 18 = 0. The value of b_xy is

(a) - 1/2

(b) - 3 /4

(c) 5/6

(d) 4/18

@Ray :ans for 1 st one I've posted (but i want the reason)

2) u r wrong check the ans i posted

but wont the g₀ there be g/16 sandipan,given that h=3R?
g₀=g(1+h/R)^-2=g(1+3)^-2=g/16
so time period should be 4 times that os a seconds pendulum on the face of earth,that is 8 s.

2
.amplitude is maximum when freq. of d external frequency is equal to the natural freq. of the body, i.e, at resonance
.....and energy directly varies with amplitude, hence w1=w2..

[It's der in syllabus]

forced amplitude is der ??I thought it wasnt sry

Regression equation se coefficient nikaalna...I had posted all that info in a BITS math thread.
http://www.targetiit.com/iit-jee-forum/posts/maths-15931.html

Basically the slope of the regression line is the regression coefficient b_xy.
b_xy = -3/4 here.
It should be b_yx waise....b_xy is for regression line of X on Y. This is regression line of Y on X. Both b's are different.

1) mein do we have to use Stefan's law?