Which describes an object in projectile motion? check all that apply. gravity acts to pull the object down. the object moves in a straight path. the forward velocity of the object is 0 m/s. the object’s inertia carries it forward. the path of the object is curved. the object moves both forward and up.

Gravity acts to pull the object down.

The object’s inertia carries it forward.

The path of the object is curved.

Explanation:

The motion of a projectile consists of two independent motion:

- A uniform motion along the x (horizontal) direction, with constant velocity equal to the horizontal component of the initial velocity of the object

- An accelerated motion along the y (vertical) direction, with constant acceleration equal to the acceleration of gravity (g = 9.8 m/s^2, downward), so with a vertical velocity increasing. This acceleration is due to the presence of the force of gravity, that pulls the object down.

So the following statements are true:

Gravity acts to pull the object down.

The object’s inertia carries it forward. --> in fact, there are no forces along the horizontal direction, so the object continues its uniform motion due to inertia

The path of the object is curved. --> in fact, the composition of the two motions (uniform along the x-axis and accelerated along the y-axis) gives a curved trajectory (specifically, a parabolic trajectory).

an ion is a charged atom or molecule. it is charged because the number of electrons do not equal the number of protons in the atom or molecule. an atom can acquire a positive charge or a negative charge depending on whether the number of electrons in an atom is greater or less then the number of protons in the atom.

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