Well, the 20 seconds gives us enough information to actually calculate the power she has on her feet :)
Well, the work is 500*15=7500J, that is 7.5 kJ or about 18 calories (1 cal is 418J?) The power is that 7.5 kJ divided by 20 seconds: 375W. That's... OK, I suppose...
Answer:
. living things only have energy : true.
Answer:
Explanation:
First, we can find the mass of the object in air
Since W = mg
m = W/g = (8.9)/(9.8) = 0.908 kg
Then, by Archimedes principle, we can find its volume. The volume is found by the weight of the water displaced by the formula
W = Vρg
The Weight is the difference in scale readings. The density of water is 1000 kg/m3
(8.9- 7.8) = V(1000)(9.8)
Thus V = 1 X 10-4 m3
Then, since density is mass / volume
ρ = 0.908/1 X 10-4
ρ = 8254 kg/m3 which is 8 X 103 kg/m3
The density of gold is 19.3 X 103 kg/m3
Since those densities are not the same, the crown is either hollow or not pure gold
The wavelength of the radio wave is 0.303 m.
<h3>
Wavelength</h3>
The wavelength of the wave is the distance traveled by the wave.
c = fλ
where;
- c is speed of light = 3 x 10⁷ m/s
- f is frequency
- λ is wavelength
λ = c/f
λ = (3 x 10⁷ ) / (99 x 10⁶)
λ = 0.303 m
Thus, the wavelength of the radio wave is 0.303 m.
Learn more about wavelength here: brainly.com/question/10728818