Force Needed to Hold Rocket Down

In summary, the force needed to hold the rocket down is equal to the thrust produced by the fuel burning at a rate of 5.0 kg/s and an exhaust speed of 2.8 km/s, plus the force of gravity (9.8 kN). However, without the specific values for the mass flow rate and exhaust speed, the exact force cannot be determined.
  • #1
joel amos
104
0
Q: The motors of a 1,000 kg rocket standing vertically on the ground are being tested. Fuel is being burned at the rate of 5.0 kg/s with an exhaust speed of 2.8 km/s. Find the force needed to hold the rocket down.

Attempt: I'm not really sure how to go about this question. I've thought about it a lot, but don't understand how to solve it. I think the force needed to hold it down would be equal to the natural force plus mg (9.8 kN), but I'm not sure how to find the natural force with the given information of the combustion rate and exhaust speed.

Thanks for helping!
 
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  • #2
Thrust = (dm/dt)V, where dm/dt is the mass flow rate and V is the exhaust speed.
 
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FAQ: Force Needed to Hold Rocket Down

What is the force needed to hold a rocket down?

The force needed to hold a rocket down depends on several factors, including the weight of the rocket, the force of gravity, and any additional external forces acting on the rocket. It also varies depending on the type and strength of the materials used to secure the rocket.

How is the force needed to hold a rocket down calculated?

The force needed to hold a rocket down can be calculated using Newton's second law of motion, which states that force equals mass times acceleration (F=ma). In this case, the force needed to hold a rocket down is equal to the weight of the rocket multiplied by the acceleration due to gravity.

What is the role of friction in holding a rocket down?

Friction plays a crucial role in holding a rocket down, as it provides the necessary resistance against the force of the rocket trying to move upwards. Without friction, the rocket would easily slip or slide, making it difficult to hold it in place.

Does the force needed to hold a rocket down change during liftoff?

Yes, the force needed to hold a rocket down changes during liftoff. As the rocket engines ignite and produce thrust, the force pushing the rocket upwards increases, requiring more force to hold it down. The amount of force needed to hold the rocket down gradually decreases as the rocket gains altitude and the force of gravity decreases.

How does the force needed to hold a rocket down differ for different types of rockets?

The force needed to hold a rocket down can vary for different types of rockets, depending on their weight, shape, and propulsion system. For example, a heavier rocket with a more powerful propulsion system would require more force to hold it down compared to a smaller and lighter rocket. Additionally, the force needed to hold down a rocket with a cylindrical shape may differ from that of a rocket with a cone-shaped or spherical design.

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