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A certain ideal gas has C_(v, m) = a + bT, where a = 25 J/(mol. K) and b = 0.03 J(mol.K^2 ). Let 2 mole of this gas go from 300 K and 2 litre volume to 600 K and 4 litre. ΔS_(gas) is

$A certain ideal gas has C_{v, m} = a + bT,$ $where a = 25 J / (mol . K) and b = 0.03$ $J (mol . K^{2}) . Let 2 mole of this gas go$ $from 300 K and 2 litre volume to 600 K$ $and 4 litre . Δ S_{gas} is$

Question Number 23707 Answers: 1 Comments: 4

Two blocks A and B of mass 1 kg and 2 kg respectively are connected by a string, passing over a light frictionless pulley. Both the blocks are resting on a horizontal floor and the pulley is held such that string remains just taut. At time t = 0, a force F = 20t N, starts acting on the pulley along vertically upward direction. Calculate vertical displacement of the pulley upto the instant when B loses contact with the floor.

$Two blocks A and B of mass 1 kg and$ $2 kg respectively are connected by a$ $string, passing over a light frictionless$ $pulley . Both the blocks are resting on a$ $horizontal floor and the pulley is held$ $such that string remains just taut . At$ $time t = 0, a force F = 20 t N, starts$ $acting on the pulley along vertically$ $upward direction . Calculate vertical$ $displacement of the pulley upto the$ $instant when B loses contact with the$ $floor .$

Question Number 24506 Answers: 0 Comments: 8

A spot light S rotates in a horizontal plane with a constant angular velocity of 0.1 rad/s. The spot of light P moves along the wall at a distance 3 m. What is the velocity of the spot P when θ = 45°?

$A spot light S rotates in a horizontal$ $plane with a constant angular velocity$ $of 0.1 rad / s . The spot of light P moves$ $along the wall at a distance 3 m . What$ $is the velocity of the spot P when θ = 45 ° ?$

Question Number 23700 Answers: 0 Comments: 3

If (1 − x^3 )^n = Σ_(r=0) ^n a_r x^r (1 − x)^(3n−2r) , then the value of a_r , where n ∈ N is (1)^n C_r ∙3^r (2)^n C_(3r) (3)^n C_(r−1) 2^(r−1) (4)^n C_r 2^r

$If {(1 - x^{3})}^{n} = \underset{r = 0}{\sum^{n}} a_{r} x^{r} {(1 - x)}^{3 n - 2 r}, then$ $the value of a_{r}, where n \in N is$ $(1)^{n} C_{r} \cdot 3^{r}$ $(2)^{n} C_{3 r}$ $(3)^{n} C_{r - 1} 2^{r - 1}$ $(4)^{n} C_{r} 2^{r}$

Question Number 23694 Answers: 0 Comments: 0

Calculate the lattice enthalpy of MgBr_2 . Given that Enthalpy of formation of MgBr_2 = −524 kJ mol^(−1) Sublimation energy of Mg = +2187 kJ mol^(−1) Vaporisation energy of Br_2 (l) = +31 kJ mol^(−1) Dissociation energy of Br_2 (g) = +193 kJ mol^(−1) Electron gain enthalpy of Br = −331 kJ mol^(−1)

$C a l c u l a t e t h e l a t t i c e e n t h a l p y o f {M g B r}_{2} .$ $G i v e n t h a t$ $E n t h a l p y o f f o r m a t i o n o f {M g B r}_{2} = - 524$ $k J {m o l}^{- 1}$ $S u b l i m a t i o n e n e r g y o f M g = + 2187$ $k J {m o l}^{- 1}$ $V a p o r i s a t i o n e n e r g y o f {B r}_{2} (l) = + 31$ $k J {m o l}^{- 1}$ $D i s s o c i a t i o n e n e r g y o f {B r}_{2} (g) = + 193$ $k J {m o l}^{- 1}$ $E l e c t r o n g a i n e n t h a l p y o f B r = - 331$ $k J {m o l}^{- 1}$