Answer:
The person with locked legs will experience greater impact force.
Explanation:
Let the two persons be of nearly equal mass (say m)
The final velocity of an object (person) dropped from a height H (here 2 meters) is given by,
(
= acceleration due to gravity)
which can be derived from Newton's equation of motion,

Now, the time taken (say
) for the momentum (
) to change to zero will be more in the case of the person who bends his legs on impact than who keeps his legs locked.
We know that,

Naturally, the person who bends his legs will experience lesser force since
is larger.
Answer: A and B
Explanation:
Electromagnetic radiations are examples of electromagnetic waves with increasing frequency and decreasing wavelength in the following order radiowaves - infrared waves - visible lights - ultraviolet rays- x-rays - gamma rays.
They did not require material medium for their propagation.
The statement above shows that EM radiations possesses different wavelengths and frequency.
Answer: Condensation of moisture in the air onto the glasses.
Explanation:
When you come from a cold environment into a warm ski lodge, the glasses are at a much lower temperature than that of the lodge.
Because the air in the room contains moisture (water vapor), it condenses on a surface whose temperature is lower than the dew point of the room.
The frequency doesn't change. If the wavespeed increases, then the wavelength must also increase ... It's just the distance the wave travels during each complete wiggle.
Answer:
Air is a mixture.
Explanation:
Air is a homogeneous mixture. It is made up of gaseous substances such as nitrogen, oxygen, and smaller amounts of others.
Carbon dioxide is a pure substance, not a mixture.
Carbon is another pure substance, it cannot be separated into other substances.
Oxygen is just oxygen, it does not contain any other substance.