A 500 g ball moves horizontally with velocity v_𝓍 = ( 15 m) / (t + 1 s) for t > 0 s. What is the net force on the ball at t = 1 s?

(II) A 3.0-kg object has the following two forces acting on it:

${\vec{F}}_1=(16\hat{i}+12\hat{j})\text{N}$

${\vec{F}}_2=(-10\hat{i}+22\hat{j})\text{N}$

If the object is initially at rest, determine its velocity $\overrightarrow{v}$ at t = 4.0s .

Which of the following statements about dynamics is correct?

A rocket traveling 1950 m/s away from the Earth at an altitude of 6400 km fires its rockets, which eject gas at a speed of 1200 m/s (relative to the rocket). If the mass of the rocket at this moment is 25,000 kg and an acceleration of 1.5 m/s² is desired, at what rate must the gases be ejected?

According to Newton's Second Law, if several objects all have the same mass ($m$) and different net forces ($F\_\mathrm{net}$) are applied to each, which statement is true about their accelerations ($a$)?

According to Newton's First and Second Laws, which of the following best explains how a hot air balloon controls its direction in flight?

According to Newton's First Law, when an object is in motion and no net external force acts on it, what will happen to its motion?