Conceptual Physics

Variables

All the forces on Rocket Guy are directed along the y axis.

What is the strategy?

1. Determine the net force on Rocket Guy.


2. Determine Rocket Guy’s mass.


3. Use Newton’s second law to find his acceleration.

Physics principles and equations

Newton’s second law

ȈF=ma

Step-by-step solution

We start by determining the net force on Rocket Guy.

Now we find Rocket Guy’s mass.

Finally we use Newton’s second law to calculate Rocket Guy’s acceleration.

thrust FT = 1250 N

weight ímg = í905 N

mass m

acceleration a

Step Reason

1. ȈF = FT + mg calculate net vertical force

2. ȈF = FT + (–mg) apply sign conventions

3. enter values and add

Step Reason

4. m = weight / g definition of weight

5. calculatem

Step Reason

6. ȈF = ma Newton's second law

7. a = ȈF/m solve for a

8. enter values from steps 3 and 5, and divide

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