Answer:
The velocity of the boy and the bicycle is 2.2 m/s.
Explanation:
We have,
Mass of child is 30 kg and the mass of bicycle is 20 kg. The combined momentum of the child and the bicycle is 110 kg-m/s.
It is required to find the velocity of the boy and the bicycle. The momentum of an object is given in terms of mass and its velocity. So,
M is combined mass of child and bicycle
So, the velocity of the boy and the bicycle is 2.2 m/s.
Answer:
b.) All these technologies use radio waves, including high-frequency microwaves
d.) Microwave ovens emit in the same frequency band as some wireless Internet devices.
e.) The radiation emitted by wireless Internet devices has the shortest wavelength of all the technologies listed above.
f.) All these technologies emit waves with a wavelength in the range of 0.10 to 10.0 m.
Explanation:
For option D. The frequency range of microwave ovens is 2450 MHz = 2.4 GHz, which intersects with wireless internet technology with range of 2.4 to 2.6 GHz.
For E, wavelenght and frequency are inversely proportional. Wireless internet service has the greatest frequency band and hence the shortest wavelenght band.
For F, in all these radiations, the highest Freq is 2.6 GHz and the lowest is 40 MHz. Wavelenght is speed of light (3x10^8 m/s) divided by the frequency.
2.6 GHz = 2.6x10^9 Hz
Wavelenght = 3x10^8 ÷ 2.6x10^9 = 0.1 m
40 MHz = 40x10^6
Wavelenght = 3x10^8 ÷ 40x10^6 = 7.5 m
Creatine phosphate can supply the energy needs of a working muscle at a very high rate, but only for about 8–10 seconds.
All the colors of the visible spectrum
