One end of copper rod is in contact with water at 100 °C and the other end in contact with ice at 0 °C. The length of the rod is 100 cm.

We know that R = ρl/A R ∝ l R1/R2 = l1/l2 Given ∵ l2 = 2l1 R1 = 0.60 hm R2/R1 = l2/l1 R2/R1 = 2l1/l1 R2 = 2 R1 R2 = 2 x 0.60 R2 = 1.2 hm

Correct Answer - `(i) 20 cm (ii) 26 cm (iii) 104 cm `

Correct Answer - (a) 9.5 सेमी: `" "`(b) 6.5 सेमी:

Correct Answer - (i) 20 cm (ii) 26 cm (iii) 104 cm

Correct option is: (B) 100 °C/m

(B) 68 cm LCu αCu ∆T = LAl αAl ∆T ∴ 88 × (1.7 × 10-5) = LAl(2.2 × 10-5) ∴ LAl = \(\frac{88\times1.7}{2.2}\) ∴ LAl = 68 cm

(A) 136 km When the piece of ice falls from the height h, it possesses potential energy, mgh. This P.E. is converted to heat energy. ∴ Q = mgh But only \(\frac{1^{th}}{4}\) of it is absorbed...

i when lenses are kept in contact then 1/f = 1/f1 + 1/f2 f = f1f2 / f1 + f2 ii. When kept distant apart, 1/f = 1/f1 +1/f2 - d/f1f2

B) Square only

Correct Answer - C Requierd volume = Volume of cone + Volume of sphere.