Question

(problem reference m.5)
a projectile is fired horizontally with an initial speed of 50.0 m/s. it strikes the ground 3.00 s later. neglect air resistance.
what is the horizontal component of the velocity of the projectile with which its strikes the ground?
29 m/s
17 m/s
50 m/s
79 m/s
40 m/s

Explanation:

Step1: Analyze horizontal motion

In projectile motion, when air - resistance is neglected, the horizontal component of velocity \(v_x\) remains constant because there is no acceleration in the horizontal direction (\(a_x = 0\)). The formula for horizontal velocity is \(v_x=v_{0x}+a_xt\). Since \(a_x = 0\), the equation simplifies to \(v_x = v_{0x}\).

Step2: Substitute the initial horizontal velocity

The initial horizontal speed \(v_{0x}=50.0\ m/s\).

Answer:

C. \(50\ m/s\)