(a)
The average exhaust speed of the rocket engine.
(a)
Answer to Problem 48PQ
The average exhaust speed of the rocket engine is
Explanation of Solution
Write the equation to find the force of thrust of the rocket.
Here,
The engine uses
Convert
Rewrite equation (I) in terms of
Conclusion:
Substitute
Therefore, the average exhaust speed of the rocket engine is
(b)
The final velocity of the rocket.
(b)
Answer to Problem 48PQ
The final velocity of the rocket is
Explanation of Solution
Write the equation to find the total mass of the rocket.
Here,
Since the fuel is decreasing the mass of fuel possess a negative sign. Hence rewrite equation (III).
Write the expression to calculate the mass of the rocket before propulsion.
Here,
Write the equation to find the final velocity of rocket.
Here,
Conclusion:
Substitute
Substitute
Substitute
Therefore, the final velocity of the rocket is
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Chapter 10 Solutions
Physics for Scientists and Engineers: Foundations and Connections
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