Question

Answer the following questions for projectile motion on level ground assuming negligible air resistance (the initial angle being neither 0º nor 90º): (a) Is the acceleration ever zero? (b) Is the acceleration ever in the same direction as a component of velocity? (c) Is the acceleration ever opposite in direction to a component of velocity?

a) (a) Yes. (b) No. (c) Yes.

b) (a) No. (b) Yes. (c) No.

c) (a) No. (b) Yes. (c) Yes.

d) (a) Yes. (b) No. (c) No.

Answer 1

In projectile motion on level ground with negligible air resistance and initial angle not 0º or 90º, acceleration due to gravity is never zero, is in the same direction as the vertical component of velocity during descent, and is opposite to this component during ascent.

Step-by-step explanation:

Projectile Motion on Level Ground

When analyzing projectile motion on level ground with negligible air resistance and the initial angle neither being 0º nor 90º, we can answer the following:

1. (a) Is the acceleration ever zero? No, the acceleration due to gravity is a constant value, directed downwards.
2. (b) Is the acceleration ever in the same direction as a component of velocity? Yes, during the downward part of the trajectory the acceleration due to gravity is in the same direction as the vertical component of the velocity.
3. (c) Is the acceleration ever opposite in direction to a component of velocity? Yes, during the upward part of the trajectory the acceleration due to gravity is opposite to the vertical component of the velocity.

Therefore, the correct option is (c): (a) No, (b) Yes, (c) Yes.