Answer: 0.25 m/s
Explanation: Speed = wavelengt · frequency
v = λf and frequency is 1/period f = 1/T
Then v = λ/T = 5 m / 20 s = 0.25 m/s
The answer is 8.
Hope I helped.
<span>65W * 8h * 3600s/h = 1.9e6 J = 447 Cal </span>
When the truck's weight is added to the boat, the boat sinks 5 cm deeper,
and displaces additional water whose weight is equal to the weight of the
truck.
The volume of the additional displaced water is
(3.9 m) x (6.3 m) x (5.0 cm)
= (3.9 m) x (6.3 m) x (0.05 m) = 1.2285 m³ .
The weight of that much water is the weight of the truck.
Mass of 1 liter of water = 1 kilogram
1.2285 m³ = 1,228.5 liters = 1,228.5 kg of water.
Weight = (mass) x (gravity)
= (1,228.5 kg) x (9.8 m/s²) = 12,039 Newtons.
(about 2,708 pounds)
The ideal concept for solving this question is based on the Doppler effect, for which it is indicated that the source's listening frequency changes as the distance and the relative speed between the receiver and the transmitter are also changed. However, if the relative velocity between the two objects is zero as in the particular case presented (since both travel at 75km / h) we have that there will be no change in frequency.
Therefore the frequency that I hear and that my sister would listen would be the same.
