Answer:
105 m/s
Explanation:
Given that the speed of train A, = 45 m/s from west to east.
Speed of train B, = 60 m/s from east to west.
Train B is moving in the opposite direction with respect to the speed of train A. Assuming that the speed from east to west direction is positive.
So, the speed of train A from east to west= - 45 m/s
The speed of train B w.r.t train A m/s
Hence, the speed of train B w.r.t train A is 105 m/s from east to west.
Answer:
2.68 hours
Explanation:
A.) Suppose the wind blows out from the west (with the air moving east). The pilot should then head her plane to northwest direction to move directly north.
B.) Given that plane flies at a speed of 102 km/h in still air. And the wind blows out from the west (with the air moving east) at a speed of 46 km/h.
The plan resultant speed can be calculated by using pythagorean theorem.
Resultant Speed = Sqrt( 102^2 + 46^2 )
Resultant Speed = Sqrt( 12520)
Resultant speed = 111.89 km/h
From the definition of speed,
Speed = distance/time
Where distance = 300 km
Substitute the resultant speed and the distance into the formula.
111.89 = 300/time
Time = 300/111.89
Time = 2.68 hours
Therefore, it take her 2.68 hours to reach a point 300 km directly north of her srarting point
This question involves the concepts of dynamic pressure, volume flow rate, and flow speed.
It will take "5.1 hours" to fill the pool.
First, we will use the formula for the dynamic pressure to find out the flow speed of water:
where,
v = flow speed = ?
P = Dynamic Pressure = 55 psi = 379212 Pa
= density of water = 1000 kg/m³
Therefore,
v = 27.54 m/s
Now, we will use the formula for volume flow rate of water coming from the hose to find out the time taken by the pool to be filled:
where,
t = time to fill the pool = ?
A = Area of the mouth of hose = = 1.98 x 10⁻⁴ m²
V = Volume of the pool = (Area of pool)(depth of pool) = A(1.524 m)
V = = 100.1 m³
Therefore,
<u>t = 18353.5 s = 305.9 min = 5.1 hours</u>
Learn more about dynamic pressure here:
brainly.com/question/13155610?referrer=searchResults
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