16) A body of mass 3.14 kg is suspended form one end of a wire of length 10 m. The radius if cross - section of the wire is changing uniformly from 5×10-4 m at the top (i.e. point of suspension) to 9.8×10-4 mat the bottom. Young's modulus of elasticity is 2×1011 N/m2. The change of length of the wire is. (a) 4×10-3 m(b) 3×10-3 m(c) 10-3 m(d) 2×10-3 m
Q.40. In which of the following electrical devices electromagnetic motor is used?
(A) Bulb
(B) Heater
(C) Transformer
(D) Washing Machine
16) A body of mass 3.14 kg is suspended form one end of a wire of length 10 m. The radius if cross - section of the wire is changing uniformly from at the top (i.e. point of suspension) to at the bottom. Young's modulus of elasticity is The change of length of the wire is.
Q.10. If the work done in stretching a wire by 1 mm is 2 J, then work necessary for stretching another wire of same material but with double radius of cross-section and half of the length by 1 mm is
(a) 8 J
(b) 16 J
(c) 4 J
(d) 32 J