What happens to the y component of a projectile's velocity as the projectile travels through the air? and What one condition must apply before you can use the range equation?

A marksman fires a practice round from A toward a target B. If the target diameter is 240 mm and the target center is at the same altitude as the end of the rifle barrel, determine the range of "shallow" launch angles for which the round will strike the target. Neglect aerodynamic drag and assume that the round is directed along the vertical centerline of the target. (Note: The word "shallow" indicates a low-flying trajectory for the round.) Answers: i 845 m/s 0 1510 m °≤0s i B O

A mass, m = 1 Kg and initial velocity u =10m/s moving to the right collides with another mass, m2=1 Kg and initial velocity U2= 10m/s moving to the left as shown in the figure below. Find the velocities (vi and v2) of the two masses after collision assuming a perfectly elastic collision. (Hint: Use both conservation of momentum and conservation of energy). a, =10m/s Uz = -10m/s %3D m2 = IKg M= 0 NOTE U, is along +n, tahen as 10mis Uz is along - n, theefave take it at - 10m/s

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