Force Needed to Hold Rocket Down

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To determine the force needed to hold a 1,000 kg rocket down, the thrust generated by the rocket's engines must be calculated using the formula Thrust = (dm/dt)V, where dm/dt is the mass flow rate of fuel (5.0 kg/s) and V is the exhaust speed (2.8 km/s). The thrust produced is 14,000 N, which must be countered by an equal force to prevent the rocket from lifting off. Additionally, the gravitational force acting on the rocket is 9,800 N. Therefore, the total force required to hold the rocket down combines the thrust and gravitational force, resulting in a need for 23,800 N to keep the rocket stationary.
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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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Thrust = (dm/dt)V, where dm/dt is the mass flow rate and V is the exhaust speed.
 
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