Answer:
The velocity of the boat with respect to the ground is 3 km/h
Explanation:
The speed of an object is different depending on the reference system you use. This is called relative speed.
A boat travels upstream, this means that it moves in the opposite direction to the river current.
A boat travels upstream, this means that it moves in the opposite direction to the river current. Then, if the boat moves in the positive direction of the x axis at 10 km / h with respect to the water of a river, the water flows in the negative direction of the x axis at 7 km / h with respect to the ground.
This causes the speed of the boat relative to the ground to be calculated as follows:
<em>VbG = Vbw - VwG
</em>
where VbG is the speed of the boat relative to the ground, Vbw is the speed of the boat relative to the water of the river and VwG is the speed of the water relative to the ground.
So: VbG=10 km/h – 7 km/h
<u><em>VbG= 3 km/h
</em></u>
The direction of this velocity is in the positive x-direction.
answer:They are too close to the sun!
Explanation:Because Mercury is so close to the Sun and its gravity, it wouldn't be able to hold on to its own moon. Any moon would most likely crash into Mercury or maybe go into orbit around the Sun and eventually get pulled into it.Same with Venus!
<span>Pitch and frequency are more or less the same thing - high pitch = high frequency.
The freqency of vibration of a string f = 1/length (L) so as length decreases the frequency increases.</span>
Answer:
F = Force (Measured in Newtons, N), m = Mass (Measured in kilograms, kg), and a = acceleration (Measured in metres per second squared, 
Explanation:
This is Newton's Second Law!
Hope this helps!
PLS mark as brainliest, hope this helps!
Answer:
A) T1 = 269.63 K
T2 = 192.59 K
B) W = -320 KJ
Explanation:
We are given;
Initial volume: V1 = 7 m³
Final Volume; V2 = 5 m³
Constant Pressure; P = 160 KPa
Mass; m = 2 kg
To find the initial and final temperatures, we will use the ideal gas formula;
T = PV/mR
Where R is gas constant of helium = R = 2.0769 kPa.m/kg
Thus;
Initial temperature; T1 = (160 × 7)/(2 × 2.0769) = 269.63 K
Final temperature; T2 = (160 × 5)/(2 × 2.0769) = 192.59 K
B) world one is given by the formula;
W = P(V2 - V1)
W = 160(5 - 7)
W = -320 KJ