(adsbygoogle = window.adsbygoogle || []).push({}); I AM NOT INTERESTED IN DIRECT ANSWERS! I'm just stuck on how to process these questions and just need a little guidance on what I'm doing wrong. I will be forever indebted and I am more interested in learning how to solve for these. Thank you!

1. A person weighing 0.9 kN rides in an elevator that has a downward acceleration of 2.6 m/s2.The acceleration of gravity is 9.8 m/s2. What is the magnitude of the force of the elevator floor on the person? Answer in units of k

1a. Relevant equations

f=m x a

1b. The attempt at a solution

Find mass of person (should be 900 N) but should I find the mass in kg?

Combine both accelerations and multiply by mass in kg?

2.When you drop a 0.35 kg apple, Earth exerts a force on it that accelerates it at 9.8 m/s2 toward the earth’s surface. According to Newton’s third law, the apple must exert an equal but opposite force on Earth.

If the mass of the earth 5.98 × 1024 kg, what is the magnitude of the earth’s acceleration toward the apple?

Answer in units of m/s2.

2a. Relevant equations.

f= m x a?

2b. Attempt

The force the apple creates is 3.43. Do I set that equal to Eaarth's force and divide by Earth's mass? I get something like 5.74e-25. That can't be right.

3.The force of friction acting on a sliding crate is 232 N. How much force must be applied to maintain a constant velocity? Answer in units of N

3a. Equation

Not sure which one to use.

3b.Attempt

Do I find the mass of the crate? Acc. has to be 9.8 but how would i find for constant velocity?

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# Newton's Laws Questions + Friction. Very tricky and help appreciated!

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