Physics - Study Mode

[#321] Flemings ''Left hand Rule" is associated with the effect of
Correct Answer

(D) Magnetic Field on current

Explanation

Solution: Flemings ''Left hand Rule" is associated with the effect of magnetic field on current.

[#322] The oil in the wick of lamp rises due to
Correct Answer

(B) Pheonomenon of capillarity

Explanation

Solution: The oil in the wick of an oil lamp rises up due to capillary action. This effect is due to surface tension of liquids. The wick here acts as a capillary tube

[#323] Which of the following devices can be used to detect radiant heat ?
Correct Answer

(D) Thermopile

Explanation

Solution: Based on the thermoelectric effect, the thermopile can be used as a heat sensor to measure thermal radiation. A thermopile is made of thermocouple junction pairs connected electrically in series. Thermocouples near the ground measures radiant energy.

[#324] Shock-absorbers are usually made of steel as it :
Correct Answer

(C) Has higher elasticity

Explanation

Solution: A shock absorber is a mechanical device designed to smooth out or damp shock impulse, and dissipate kinetic energy. Steel is an alloy made by combining iron and other elements, the most common of these being carbon. When carbon is used, its content in the steel is between 0.2% and 2.1% by weight, depending on the grade. Varying the amount of alloying elements and the form of their presence in the steel (solute elements, precipitated phase) controls qualities such as the higher elasticity, hardness, ductility, and tensile strength of the resulting steel.

[#325] The dimensional formula ML –1 T –2 corresponds to
Correct Answer

(A) Modulus of elasticity

Explanation

Solution: The dimensional formula ML -1 T -2 corresponds to modulus of elasticity.