Step 1: Identifying Karbate.
Karbate is an alloy of copper and nickel, commonly used in various industrial applications due to its corrosion resistance and durability.
Step 2: Explanation of options.
- (A) Karbate is correctly identified as an alloy of copper and nickel.
- (B) Chemically impregnated carbon is not Karbate.
- (C) High silicon iron is not related to Karbate.
- (D) Karbate is not an alloy of copper, tin, and zinc.
Final Answer: \[ \boxed{\text{A) an alloy of copper and nickel}} \]
A weight of $500\,$N is held on a smooth plane inclined at $30^\circ$ to the horizontal by a force $P$ acting at $30^\circ$ to the inclined plane as shown. Then the value of force $P$ is:
A steel wire of $20$ mm diameter is bent into a circular shape of $10$ m radius. If modulus of elasticity of wire is $2\times10^{5}\ \text{N/mm}^2$, then the maximum bending stress induced in wire is: