The area of cross-section of a steel wire (Y=2.0×10¹¹ N/m²) is 0.1 cm². The force required to double its length will be
Options
(a) 2×10¹² N (b) 2×10¹¹ N (c) 2×10¹⁰ N (d) 2×10⁶ […]
Shearing stress causes change in
Options
(a) Length (b) Breadth (c) Shape (d) Volume
Correct Answer:
Shape
Explanation:
No explanation available. Be the first to write the explanation for this question by commenting […]
A black body radiates 20 W at temperature 227⁰C. It temperature of the black body is changed to 727⁰C, then its radiating power will be
Options
(a) Lamp black (b) Platinum black (c) Highly […]
If the radius of star is R and it acts as a black body, what would be the temperature of the star, in which the rate of energy protection is Q?
Options
(a) Q […]
Water rises in a vertical capillary tube up to a height of 2.0 cm. If the tube is inclined at an angle of 60⁰ with the vertical, then up to what length the water will […]
The total radiant energy per unit area, normal to the direction of incidence, received at a distance R from the centre of a star of radius r, whose outer surface radiates as a black body […]
Heat is flowing through a rod of length 50 cm and area of cross-section 5 cm². Its ends are respectively at 25⁰C and 125⁰C. The coefficient of thermal conductivity of the rod is 0.092 k.cal/m […]
A liquid wets a solid completely. The meniscus of the liquid in a sufficiently long tube is
Options
(a) Flat (b) Concave (c) Convex (d) Cylindrical
Correct Answer:
Concave
Explanation:
Meniscus of liquid which […]
A black body at 227⁰C radiates heat at the rate of 7cals/cm²s. At a temperature of 727⁰C, the rate of heat radiated in the same units will be:
Options
(a) 50 (b) 112 (c) […]
The two ends of a rod of length L and a uniform cross-sectional area A are kept at two temperatures T₁ and T₂ (T₁ > T₂). The rate of heat transfer, dQ/dt through the rod […]
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