Does the Teacher's Edition Have a Mistake in This Science Problem?

[LisaandCaiti]

I have a problem in my science book,we think the teachers edition may have a mistake? Can someone look at my problem and explain how to find the answer? I am home schooled, and like mom said, 7th grade was too many years ago!


Calculate mass: You push yourself on a skateboard with a force of 30N and accelerate at 0.5 m/s squared. Find the mass of the skateboard if your mass is 58kg.

We keep coming up with a different answer than the book. Can someone explain this so we can make sure we are doing it correctly?

Thank You!

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[mgb_phys]

The equation is force = mass * acclearation or F=ma
Since we know f and a and want m we have to re-arrange the formula this gives m=f/a
If you plug in the numbers you get m = 30N/0.5ms^-2 = 60kg
Since you have a mass of 58.5kg the mass of the skateboard is the difference.

 

[cancer501]

you divide 30n by 0.5 m/s and you will get ur anwser which you then subtaract 58 from and you will get ur anwser it will have this unit of measure kg*m/s N