In a supermarket parking lot, an employee is pushing ten empty shopping carts, lined up in a straight line. The acceleration of the carts is 0.05 m/s^2. The ground is level, and each cart has a mass of 26 kg.(adsbygoogle = window.adsbygoogle || []).push({});

a. What is the net force acting on any one of the carts?

b. Assuming friction is negligible, what is the force exerted by the fifth cart on the sixth cart?

Answers:

a. 1.3 newtons

b. 6.5 newtons

I most definitely understand the concept behind B and how to reach the answer of 6.5 newtons.

I know that to get answer A, you do F = ma = 26(0.05) =1.3 newtons....However, I am confused as to why part A is not 13 newtons.

Isn't the net force on any single cart going to be 13 newtons? My reasoning was that there are ten carts total, for a total mass of 260 kilograms.

Total mass = 10(26) = 260 kg

Fnet = total mass x acceleration = 260 x 0.05 = 13 newtons.

Don't the masses of the carts add up to give the net force on any cart??

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# F = ma, net force on shopping carts

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