doing the dynamics trolley exp. for newtons 2nd law. stuck on a couple of q's, i realise the concept but i am having trouble expressing it:)(adsbygoogle = window.adsbygoogle || []).push({});

1.why is the mass in net force=ma not just equal to the mass of the cart?

2.when calculating the force on the cart using mass times gravity, why isnt the mass of the cart included?

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# Homework Help: Simple question:S help!

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