Calculate the magnitude and direction physics

AI Thread Summary
The discussion revolves around two physics problems involving momentum and forces. The first problem concerns a rocket altering its course by expelling gas, requiring the application of conservation of momentum to determine the mass of gas needed. The second problem involves a ladder leaning against a wall, where participants are encouraged to analyze force diagrams and vector forces to calculate the ground force and the minimum angle to prevent slipping. Participants emphasize the importance of showing initial attempts and reasoning to facilitate discussion. The conversation highlights the need for a systematic approach to solving physics problems through diagram analysis and momentum principles.
mariomd
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ive been laboring over these two problems:

A 4050 kg rocket is traveling in outer space with a velocity of 126 m/s toward the Sun. It needs to alter its course by 23.2°, which can be done by shooting its rockets briefly in a direction perpendicular to its original motion. If the rocket gases are expelled at a speed of 2270 m/s relative to the rocket, what mass of gas must be expelled?

and

A uniform 6.53 m long ladder of mass 14.9 kg leans against a smooth wall.The ladder makes an angle theta = 19.5° with the ground and the ground is rough.
+Calculate the magnitude and direction (relative to ground) of the force exerted by the ground on the ladder at its base.
+determine the minimum angle at which the ladder is not to slip when a 69.9 kg person stands three-fourths of the way up the ladder. The coefficient of static friction is 0.5.
 
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mariomd,

Can you post what you have done.
 
First, gamma is right, you should show us what you have tried or at least your general reasoning. For the first question, consider conservation of momentum concepts. For the second, start with some force diagrams and consider the force vectors involved. You will need to analyse vectorally.
 
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