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3 years ago

Planet a and planet b are in circular orbits around a distant star. planet a is 7.8 times farther from the star than is planet

1 answer:

6 0

To find the ratio of planetary speeds Va/Vb we need the orbital velocity formula:

V=√({G*M}/R), where G is the gravitational constant, M is the mass of the distant star and R is the distance of the planet from the star it is orbiting.

So Va/Vb=[√( {G*M}/Ra) ] / [√( {G*M}/Rb) ], in our case Ra = 7.8*Rb

Va/Vb=[ √( {G*M}/{7.8*Rb} ) ] / [√( {G*M}/Rb )], we put everything under one square root by the rule: (√a) / (√b) = √(a/b)

Va/Vb=√ [ { (G*M)/(7.8*Rb) } / { (G*M)/(Rb) } ], when we cancel out G, M and Rb we get:

Va/Vb=√(1/7.8)/(1/1)=√(1/7.8)=0.358 so the ratio of Va/Vb = 0.358.

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A car with a mass of 1,600 kg is traveling at a speed of 25 m/s. What is the momentum of

tamaranim1 [39]

40,000 kg m/s
Momentum = mass * velocity
= 1600 * 25
= 40,000

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3 years ago

Which properties define light as a wave?

Naddik [55]

Properties that define the light is a wave are

1. Speed : speed of light is 300,000 Km /s, It is most fundamenta property of light to define light is a wave

2. Reflection: Light particles or photons reflect off the particles or masses are continue to travel at the same speed.

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3 years ago

) A 73-mH solenoid inductor is wound on a form that is 0.80 m long and 0.10 m in diameter. A coil having a resistance of is tigh

Aleonysh [2.5K]

Complete question is;. A 73mH solenoid inductor is wound on a form that is 0.80m long and 0.10m in diameter a coil having a resistance of 7.7 ohms is tightly wound around the solenoid at its center the mutual inductance of the coil and solenoid is 19μH at a given instant the current in the solenoid is 820mA and is decreasing at the rate of 2.5A/s at the given instant what is the induced current in the coil

Answer:

6.169 μA

Explanation:

Formula for induced EMF is given by the equation;

EMF = M(di/dt). We are given;

di/dt = 2.5 A/s

M = 19μH = 19 × 10^(-6) H

Thus;

EMF = 19 × 10^(-6) × 2.5.

EMF = 47.5 × 10^(-6) V

Formula for current is;

i = EMF/R. R is resistance given as 7.7 ohms.

Thus; i = 47.5 × 10^(-6)/7.7

i = 6.169 μA

5 0

3 years ago

Una cámara fotográfica analógica (no digital) tiene dos lentes intercambiables. Uno de foco 55mm y el otro de 200 mm. Toma una f

Sergeu [11.5K]

Answer:

f = 55mm, h ’= -9.89 cm

f = 200 mm, h ’= 42.5 cm

Explanation:

For this exercise let's start by finding the distance to the image, using the equation of the constructor

$\frac{1}{f} = \frac{1}{p} + \frac{1}{q}$

where f is the focal length, p and q are the distances to the object and image, respectively

lens with f₁ = 55mm = 0.55cm

$\frac{1}{q} = \frac{1}{f} - \frac{1}{p}$

$\frac{1}{q_1}$ = $\frac{1}{0.55} - \frac{1}{10}$

$\frac{1}{q_1}$ = 1.718

q₁ = 0.582 m

lens with f₂ = 200mm = 2m

$\frac{1}{q_2}$ = $\frac{1}{2} - \frac{1}{10}$

$\frac{1}{q_2}$ = 0.4

q₂ = 2.5 m

the magnification of a lens is given by

m = $\frac{h'}{h} = - \frac{q}{p}$

h ’= $- \frac{q}{p} \ h$

let's calculate for each lens

f = 55mm

h '= - 0.582 / 10 1.7

h ’= 0.0989 m

h ’= -9.89 cm

f = 200 mm

h '= - 2.5 / 10 1.7

h ’= -0.425 m

h ’= 42.5 cm

The negative sign indicates that the image is real and inverted

4 0

3 years ago

how difficult is it to start a heavy lorry moving and to stop it moving? (choose one answer from the image provided)

ale4655 [162]

Answer:

option B

Explanation:

3 0

3 years ago