Tag: physics

Quizzes (598) Questions (13441)

Questions Related to physics

Multiple choice physics pressure pressure in fluids pressure in liquids introduction to pressure

Fill in the blank spaces by choosing the correct words from the options given below.

The hulls of the______are made very strong to withstand huge pressure exerted by the sea water. 

  1. $liquids$

  2. $gases$

  3. $submarines$

  4. All of the above
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Submarines.
The hull of Submarines are specially Strengthened to prevent it from collapsing from the high pressure of the water outside while submerged. Roughly every $30$ feet of depth under water adds another atmosphere of inward pressure on the hull.

Multiple choice physics pressure pressure in fluids pressure in liquids introduction to pressure

A deep sea diver may hurt his ear drum during diving because of:

  1. lack of oxygen

  2. more atm pressure

  3. more water pressure

  4. all of the above
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The pressure at a depth $h$ below the surface of water is given by 

$P=P _0+h\rho g$
Hence as the depth increases, the pressure increases.
Due to this increased pressure, as the diver goes deeper in sea water, the ear drum may get damaged.

Multiple choice physics pressure pressure in fluids pressure in liquids introduction to pressure

In cities water supply from an overhead tank to.the houses is done due to:

  1. difference in pressure

  2. gravitational force

  3. decrease of friction in pipes

  4. flow of liquid
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The water in an overhead tank has higher gravitational potential to compared to water which finally flows out of the taps in the houses. 
The water moves due to this decrease in gravitational potential energy of water by flowing out of taps, or, the water is supplied by the gravitational force acting on water.

Multiple choice physics force and pressure pressure in fluids pressure in liquids introduction to pressure

Fluids include

a) Solids    
b) Liquids  
c) Gases

  1. a and b

  2. b and c

  3. a and c

  4. All the above
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

A fluid is a substance that has no fixed shape and yields easily to external pressure; a gas or  a liquid, or, which can easily flow.

It is due to this property of variation of pressure along a fluid that it exerts a buoyant force on a body placed inside it. 

Multiple choice physics static electricity properties of charges charge properties of charge

A gold coin has a charge of $+10^{-4} C$. The number of electrons removed from it is:

  1. $10^6$

  2. $625 \times 10^{12}$

  3. $1.6 \times 10^{-25}$

  4. $1.6 \times 10^{13}$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The total charge of electrons removed from the coin would be equal to the positive charge acquired by the coin.

Thus, $10^{-4}C=n\times 1.6\times 10^{-19}C$
$\implies n=625\times 10^{12}$

Multiple choice physics static electricity properties of charges charge properties of charge

Choose best option about cavity for a charged metallic sphere: 

  1. Net field inside the cavity is zero

  2. Net field inside the metal is non-zero constant

  3. Potential inside the metal is constant

  4. Potential outside metal is constant
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Inside the cavity of charged measure sphere net electric field is non zero constant.

$\therefore $ Option $A$ is correct.

Multiple choice physics static electricity properties of charges charge properties of charge

Two charges 2$\mathrm { uC }$ and 1$\mathrm { \mu }C$ are placed at adistance of 10$\mathrm { cm }$ . The position of the third charge from2$\mu \mathrm { C }$ between them so that it does not experience any force

  1. $7cm$

  2. $2cm$

  3. $5.858cm$

  4. $8cm$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

For a charge to experience no force, the electric fields from the two charges must be equal and opposite. Setting k(2)/x^2 = k(1)/(10-x)^2 leads to 2(10-x)^2 = x^2, which simplifies to sqrt(2)(10-x) = x. Solving for x gives x = 10*sqrt(2)/(1+sqrt(2)) approximately 5.858 cm.