Which type of mine involves digging tunnels and shafts deep underground?
1 answer:
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Displacement measures how far it is from the starting point and the final location, which in this case is the distance between Honolulu and Los Angeles. The difference between distance and displacement is that distance measures how far the object actually travels. For example, the airplane may not fly in a straight line and it may have detours, making the distance much greater than the displacement.
On the other hand, the plane could fly at different speeds at different periods of time. It will be so much more complicated if we have to calculate it. That's why this question only asks you to calculate the average velocity of the plane, ie.
So, we have
the required average velocity =
= 511.6 miles/hour
Hope this helps!
Answer:
The total power they will consume in series is approximately 2.257 W
Explanation:
The connection arrangement of the headlight and the engine starter = Parallel to the battery
The voltage of the battery, V = 12.0 V
The power at which the headlight operates in parallel, = 38 W
The power at which the kick starter operates in parallel, = 2.40 kW
We have;
P = V²/R
Where;
R = The resistance
V = The voltage = 12 V (The voltage is the same in parallel circuit)
For the headlight, we have;
R₁ = V²/ = 12²/38 = 72/19
R₁ = 72/19 Ω
For the kick starter, we have;
R₂ = V²/ = 12²/2.4 = 60
R₂ = 60 Ω
When the headlight and kick starter are rewired to be in series, we have;
Total resistance, R = R₁ + R₂
Therefore;
R = ((72/19) + 60) Ω = (1212/19) Ω
The current flowing, I = V/R
∴ I = 12 V/(1212/19) Ω = (19/101) A
We note that power, P = I²R
In the series connection, we have;
= I² × R₁
∴ = ((19/101) A)² × 72/19 Ω = 1368/10201 W ≈ 0.134 W
The power at which the headlight operates in series, ≈ 0.134 W
= ((19/101) A)² × 60 Ω = 21660/10201 W ≈ 2.123 W
The power at which the kick starter operates in series, ≈ 2.123 W
The total power they will consume, =
+
Therefore;
≈ 0.134 W + 2.123 W = 2.257 W
Answer:
Explanation:
By conservation of energy, the sum of the kinetic and gravitational potential energies at the surface of the Earth must be equal than their sum at infinity, so we have:
Where is the gravitational constant,
and
are the mass and radius of the Earth, <em>m </em>is the mass of the particle,
its velocity at the surface of the Earth (which would be its escape velocity) and
and
are the velocities and distance at infinity, which would be null and infinity respectively, so the right hand side of our equation is 0J, which leaves us with:
Also, since the force the molecule experiments is the force of gravity (disregarding drag), we can write its weight in terms of Newton's Law of Gravitation:
Which means that:
So finally putting all together we can write:
That's true.
In fact, the resistance of a wire is given by:
where
is the resistivity of the material
L is the length of the wire
A is the cross-sectional area of the wire
We see that the resistance of the wire is inversely proportional to the cross-sectional area: A. Therefore, the narrower the wire, the smaller A, the larger the resistance. But higher resistance means that the current flowing through the wire is lower, therefore the flow of electrons in the circuit is slower, and the initial sentence is true.
In fact, the resistance of a wire is given by:
where
L is the length of the wire
A is the cross-sectional area of the wire
We see that the resistance of the wire is inversely proportional to the cross-sectional area: A. Therefore, the narrower the wire, the smaller A, the larger the resistance. But higher resistance means that the current flowing through the wire is lower, therefore the flow of electrons in the circuit is slower, and the initial sentence is true.