Tag: option b: engineering physics

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Questions Related to option b: engineering physics

Multiple choice fluid dynamics option b: engineering physics physics

Hot syrup flows faster because:

  1. Surface tension increases when temperature is increased.

  2. Viscosity decreases when temperature is increased.

  3. Viscosity increases when temperature is increased.

  4. Surface tension decreases when temperature is increased.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Hot syrup is liquid at higher temperature. We know that as temperature increases viscosity decreases for liquids. So, hot syrup flows faster as viscosity decreases.

Multiple choice fluid dynamics option b: engineering physics physics

Assertion : Water flows faster than honey.
Reason: The coefficient of viscosity of water is less than honey.

  1. Both assertion and reason are true and reason is correct explanation of assertion.

  2. Both assertion and reason are true but reason is not the correct explanation of assertion.

  3. Assertion is true but reason is false.

  4. Both assertion and reason are false.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Velocity is inversely proportional to coefficient of viscosity, $\eta$ of water is less than that of honey.
Hence, water flows faster than honey.

Multiple choice fluid dynamics option b: engineering physics physics

With increase in temperature, the viscosity of:

  1. gases decreases and liquid increases

  2. gases increases and liquid decreases

  3. both gases and liquid increases

  4. both gases and liquid decreases
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The viscosity of liquid is inversely proporional to the square of the temperature, therefore as we increase the temperature, the viscosity of liquids will decrease.


Similarly, the viscosity of gases is linearly proportional to the temperature. hence as the temperature increases, the viscosity will increase

Multiple choice fluid dynamics option b: engineering physics physics

A spaceship entering the earth's atmosphere is likely to catch fire. This is due to:

  1. The surface tension of air

  2. Air Friction

  3. The high temperature of upper atmosphere

  4. The greater portion of oxygen in the atmosphere at greater height.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

As the body enters Earth's atmosphere, it falls at very high speeds. This high speeds cause a lot of friction with the air, causing the parts to catch fire.
Option B.

Multiple choice fluid dynamics option b: engineering physics physics

When an object is dropped into a fluid, the extent of splash, due to buoyant force of fluid, depends on:

  1. sliding friction

  2. rolling friction

  3. fluid friction

  4. static friction
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The splash, due to buoyant force of a fluid depends on fluid friction.

Multiple choice fluid dynamics option b: engineering physics physics

Vehicles are streamlined to reduce 

  1. Static friction

  2. Kinetic friction

  3. Fluid friction

  4. Slidingfriction
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Fishes have streamlined shape. So, to reduce the fluid friction, the vehicles are made streamlined.

Multiple choice fluid dynamics option b: engineering physics physics

A good lubricant should be highly

  1. viscous and velocity

  2. non-viscous volatile

  3. viscous and non-volatile

  4. transparent
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

A good lubricant generally possesses the following characteristics: A high boiling point and low freezing point (in order to stay liquid within a wide range of temperatures) A high viscosity index. Thermal stability.

Multiple choice fluid dynamics option b: engineering physics physics

Two spheres $A$ and $B$ fall through the same viscous fluid. $A$ and $B$ have the same density and $B$ has the larger radius.
Then,

  1. A has the larger terminal velocity

  2. A and B have the same terminal velocity

  3. B has the larger terminal velocity

  4. Insufficient information is given to reach a conclusion.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Two spheres $A$ and $B$ fall through the same viscous fluid $A$ and $B$ have  the same density and $B$ has the larger radius the $B$ has the larger terminal velocity.

$\therefore $ Option $C$ is correct.

Multiple choice fluid dynamics option b: engineering physics physics

Ball pen and fountain pen depends respectively on principle of:-

  1. Surface tension and viscosity

  2. Surface tension and gravity

  3. Gravitation and Surface tension

  4. Surface tension and Surface tension
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Ball pens use a ball that rolls ink onto paper, relying on surface tension to keep the ink in the reservoir. Fountain pens rely on capillary action and gravity to feed ink to the nib.