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3 years ago

Why is Vy negative and not positive because I solved it and it resulted in a positive number?

Physics

1 answer:

11Alexandr11 [23.1K]3 years ago

8 0

Explanation:

You are given the initial velocity, the displacement, and the acceleration. You're looking for the final velocity. So you use the equation:

v² = v₀² + 2aΔy

When you solve for v, you take the square root. Your calculator will return a positive answer, but there are actually two possible answers: positive and negative.

v = ±√(v₀² + 2aΔy)

You must use the physical context of the problem. If we take up to be the positive direction, then v must be negative, since the projectile is moving down.

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The James Webb Space Telescope is positioned around 1.5 million kilometres from the Earth on the side facing away from the Sun.

Bad White [126]

The angular velocity depends on the length of the orbit and the orbital

speed of the telescope.

Response:

First question:

The angular velocity of the telescope is approximately 0.199 rad/s

Second question:

The telescope should accelerates away by approximately F = 0.0005·m

Third question:

The pulling force between the Earth and the satellite

<h3>What equations can be used to calculate the velocity and forces acting on the telescope?</h3>

The distance of the James Webb telescope from the Sun = 1.5 million kilometers from Earth on the side facing away from the Sun

The orbital velocity of the telescope = The Earth's orbital velocity

First question:

$Angular \ velocity = \mathbf{\dfrac{Angle \ turned}{Time \ taken}}$

The orbital velocity of the Earth = 29.8 km/s

The distance between the Earth and the Sun = 148.27 million km

The radius of the orbit of the telescope = 148.27 + 1.5 = 149.77

Radius of the orbit, r = 149.77 million kilometer from the Sun

The length of the orbit of the James Webb telescope = 2 × π × r

Which gives;

r = 2 × π × 149.77 million kilometers ≈ 941.03 million kilometers

Therefore;

$Angular \ velocity = \dfrac{29.8}{941.03}\times 2 \times \pi \approx 0.199$

The angular velocity of the telescope, ω ≈ 0.199 rad/s

Second question:

Centrifugal force force, $F_{\omega}$ = m·ω²·r

Which gives;

$F_{\omega} = m \cdot \dfrac{28,500^2 \, m^2/s^2}{149.77 \times 10^9 \, m} \approx 0.0054233 \cdot m$

$Gravitational \ force, F_G = \mathbf{G \cdot \dfrac{m_{1} \cdot m_{2}}{r^{2}}}$

Universal gravitational constant, G = 6.67408 × 10⁻¹¹ m³·kg⁻¹·s⁻²

Mass of the Sun = 1.989 × 10³⁰ kg

Which gives;

$F_G = 6.67408 \times 10^{-11} \times \dfrac{1.989 \times 10^{30} \times m}{149.77 \times 10^9} \approx 0.00592 \cdot m$

Which gives;

$F_{\omega}$ < $F_G$ , therefore, the James Webb telescope has to accelerate away from the Sun

F = $\mathbf{F_{\omega}}$ - $\mathbf{F_G}$

The amount by which the telescope accelerates away is approximately 0.00592·m - 0.0054233·m ≈ 0.0005·m (away from the Sun)

Third part:

Other forces include;

The force of attraction between the Earth and the telescope which can contribute to the the telescope having a stable orbit at the given speed.

Learn more about orbital motion here:

brainly.com/question/11069817

3 0

3 years ago

If, in general, r were calculated as r =v/i, which circuit arrangement in part a of the experiment would have the smallest error

ladessa [460]

Concept: According to Ohm's Law, the flow of electric current through a conductor is directly proportional to the potential difference across it, provided physical conditions (like temperature, pressure, volume etc.) remains same.

v = ir

or, r = v / i

Here, current (i) is measured by Ammeter which should be connected in series of any electrical circuit.

voltage (v) is measured by Voltmeter which should be connected parallel to the external resistance (r).

In the given experiment, the first arrangement of the circuit will show the smallest error because the voltmeter is connected exactly parallel to the external resistance.

In the second arrangement, the voltmeter is connected across external resistance (r) and Ammeter (A) and in this case, the voltmeter will not measure the exact potential drop across the external resistance (r). So, there would be more error.

4 0

3 years ago

Why is more energy required to vaporise 1kg of water than to melt 1kg of ice?

KiRa [710]

Answer:

cause it takes a lotof energy to melt

Explanation:

7 0

3 years ago

Read 2 more answers

Select the correct answer.

Serhud [2]

Answer:

b hope this helps

Explanation:

5 0

3 years ago

Read 2 more answers

Electromagnetic waves travel at a speed of 3.0 x 108 m/s. A radio station transmits waves

Sophie [7]

Answer:

1.2×10⁶ Hz

Explanation:

Applying,

v = λf............. Equation 1

Where v = speed of wave, λ = wavelength, f = frequency.

make f the subject of the equation

f = v/λ............... Equation 2

From the question,

Given: v = 3.0×10⁸ m/s, λ = 2.5×10² m

Substitute these values into equation 2

f = 3.0×10⁸/2.5×10²

f = 1.2×10⁶ Hz

6 0

3 years ago