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4 years ago

11

Assuming a vertical trajectory with no drag, derive the applicable form of the rocket equation for this application

1 answer:

VARVARA [1.3K]4 years ago

8 0

Answer:

The vertical trajectory is governed by Ordinary Differential Equation.

Time derivatives of each state variables.

d(d)/dt = v, d(m)/dt = -d(m-fuel)/dt, d(v)/dt = F/m.

Where V is velocity positive upwards, t is time, m is mass, m-fuel is fuel mass, F is Total force, positive upwards.

Therefore,

F = -mg - D + T, If V is positive and

F = -mg + D - T, If T is negative.

D is drag and the questions gave it as zero.

Explanation:

The two sign cases in derivative equations above are required because F is defined positive up, so the drag D and thrust T can subtract or add to F depending in the sign of V . In contrast, the gravity force contribution mg is always negative. In general, F will be some function of time, and may also depend on the characteristics of the particular rocket. For example, the T component of F will become zero after all the fuel is expended, after which point the rocket will be ballistic, with only the gravity force and the aerodynamic drag force being p

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Answer:

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3 years ago

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A 780g, 50-cm-long metal rod is free to rotate about a frictionless axle at one end. While at rest, the rod is given a short but

Semmy [17]

Answer:

9.6 rad/s

Explanation:

$L$ = length of the metal rod = 50 cm = 0.50 m

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3 years ago

To give an idea of sensitivity of the platypus's electric sense, how far from a 80nC n C point charge does the field have this m

SVETLANKA909090 [29]

The question is incomplete. The complete question is :

A platypus foraging for prey can detect an electric field as small as 0.002 N/C.

-To give an idea of sensitivity of the platypus's electric sense, how far from a +80nC point charge does the field have this magnitude?

Solution :

Given electric field, E = 0.002 N/C

Charge, Q = + 80 nC

$\therefore E = \frac{kQ}{R^2}$

or $R^2=\frac{kQ}{E}$

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3 years ago

Which is the equivalent resistance of the circuit<br><br> shown below?

Misha Larkins [42]

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3 years ago

A closely wound search coil has an area of 3.13 cm2, 135 turns, and a resistance of 61.1 Ω. It is connected to a charge-measurin

erastovalidia [21]

Answer:

Explanation:

Let the magnitude of magnetic field be B .

flux passing through the coil's = area of coil x field x no of turns

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= .086 T .

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3 years ago