A 15 Kilogram Cart and a 5 Kilogram Box: Mass and Inertia

What happens to the mass and inertia of a 15 kilogram cart on a horizontal surface when a 5 kilogram box is placed in the cart?

Increased Mass and Inertia

The mass of the cart-box system is now 20 kg (15 kg + 5 kg). The inertia of the cart-box system has also increased as the additional 5 kg box requires more force to move than just the 15 kg cart alone. So, the cart-box system has both greater mass and greater inertia than the cart alone.

Explanation

When the 5 kilogram box is placed in the 15 kilogram cart, their masses are added together to give a total mass of 20 kilograms for the cart-box system. This means that the system now has more mass to move than just the 15 kilogram cart alone. Inertia is a property of matter that describes the resistance of an object to changes in its motion. The additional mass of the box increases the inertia of the cart-box system, as more force is needed to accelerate the system compared to just the cart. Both mass and inertia are important when considering the motion of objects. The greater the mass, the more force is required to move an object. Similarly, objects with higher inertia will resist changes in their motion. In this case, adding the 5 kilogram box to the 15 kilogram cart increases both the mass and inertia of the system, making it harder to accelerate and decelerate compared to the cart alone.
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