Isha121

पहले दस तत्व हैं- H, He, Li, Be, B, C, N, O, F तथा Neइन सब तत्वों में से धातु हैं- Li तथा BeB एक मिश्रधातु है।

The following words of Mr. Hamel shocked and surprised little Franz. They were thunderclap to him. “My children, this is the last lesson I shall give you. The order has come from Berlin to teach only German in the schools of Alsace and Lorraine. The new master comes tomorrow. This is your last French lesson. I want you to be very attentive.”

Basis of bulk and weight of raw material:
(i)Heavy Industries-
(a) Brassware(b) Ship building
(c) Automobiles (d) Oil
(ii)Light Industries-
(a) Knitting needles (b) Fuse wires
(c) Electric bulb (d) Paint brushes
(e) Watches (f) Sewing machines.

Given,Number of turns, N = 20 Radius of the coil, r = 10 cm = 10 x 10–2 mMagnetic field, B = 0.10 TCurrent carried, I = 5.0 Aθ = 0° (angle between field and normal to the coil)Area of the coil, A = πr2                           = π x (10 x 10–2)2                          = π x 10–2 m2(a) Torque, τ = NIBA sin θ                   = 20 x 5.0 x 0.10 x π x 10–2 sin 0°                   = 20 x 5.0 x 0.10 x π x 10–2 x 0 = 0(b) Net force on a planer current loop in a magnetic field is always zero, as net force due to couple of force is zero. (c) If vd is the drift velocity of electron               

(a)
 For A + B-->  P
r = k [A]1/2 [B]2
The order of the reaction = 
(b) For first order reaction
k = 5.5 x 10-14 s-1
Half-life period () for the first order reaction