Answer:
22km/h
Explanation:
The speed of the keys relative to the ground will be given by the sum of speed of keys with respect to the ground and the speed of keys with respect to the skater
Given that the speed of keys with respect to the ground is 8 m/s while the speed of keys with respect to skater is 14 km/h then the relative speed which combines both speeds will be 8+14=22 km/hr
Answer:
Change the wavelength to half while keeping velocity constant or change the wave velocity to 2 times while keeping wavelength constant.
Explanation:
The frequency of a wave can be defined as the rate of change of wave speed with respect to the wavelength of the wave.
Mathematically,

Here, v is the velocity, lambda is the wavelength, and f is the frequency of the wave.
If the observer want to double the frequency of the wave, then he should increase the wave velocity two times and take wavelength constant for this case or either he should half the wavelength of the wave to take the velocity of the wave constant.
Answer: Comparing infrared and ultraviolet, ''we can say that infrared has longer wavelength and lower photon energy''
Answer:
Well, each ml of water requires one calorie to go up 1 degree Celsius, so this liter of water takes 1000 calories to go up 1 degree Celsius.
Explanation: