Tag: physics

Quizzes (598) Questions (13441)

Questions Related to physics

Multiple choice physics properties of waves longitudinal and transverse waves travelling waves types of waves

Which of the following statements are true for wave motion ?

  1. Mechanical transverse waves can propagate through all mediums

  2. Longitudinal waves can propagate through solids only

  3. Mechanical transverse waves can propagate through solids only

  4. Longitudinal waves can propagate through vacuum
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

$1.$ Mechanical transverse waves cannot propagate through all the medium. They can only propagate through solids not in gas or a liquid because there is no mechanism for driving motion perpendicular to the propagation of the wave.

$2.$ Longitudinal wave can propagate through all type of medium.
$3.$ Mechanical transverse wave can propagate through solids only.
$4.$ Longitudinal wave cannot propagate through vaccum.
Hence, option $C$ is correct.

Multiple choice physics properties of waves longitudinal and transverse waves travelling waves types of waves

A man sets his watch by the noon whistle of a factory at a distance of $1.5 km.$ Then the number of seconds his watch slower than the clock of the factory (velocity of sound $= 332 m/s$) is 

  1. $4.52 sec$
  2. $5.35 sec$
  3. $2.18 sec$
  4. $3.76 sec$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

time taken for the whistle to reach the person is $\dfrac{d}{v}$
$=\dfrac{1.5\times 1000}{332}=4.52sec$
$\therefore$ delay of his clock is $4.52s$

Multiple choice physics temperature and heat applications of heat conduction applications of insulation clothes - our necessity

Air is a good conductor of heat. True or false.

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
False
Air is bad conductor of heat. It is due to the air trapped between the cotton molecules which gives warmth on taking quilt in winter It is due to air molecules trapped between wool fabrics which provide warmth to body during winter season.
Multiple choice physics temperature and heat applications of heat conduction applications of insulation clothes - our necessity

Wearing black clothes in summer is more preferable. True or false.

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
False
Wearing black clothes in summer is not preferable as during summer there is more heat present in the atmosphere and black clothes absorb more heat comparatively. So, black clothes are not preferable during summer.
Multiple choice physics temperature and heat applications of heat conduction applications of insulation clothes - our necessity

State whether given statement is True or False
Two thin blankets are more warmer than one thick blanket

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
The blanket do not insulate; actually air insulates.
Air is trapped in the space between two thin blankets. Since air is insulator of heat, it prevents the escape of body heat. The air can't pass deeper and the layers will stop the air in two thin blankets where as there are no layers and air can pass deeper in one thick blanket. That's why two thin blankets are usually warmer than one thick blanket.