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question 5
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question 5
a projectile fired from a gun has initial horizontal and vertical components of velocity equal to 30 m/s and 40 m/s, respectively. determine the initial speed of the projectile.
60 m/s
80 m/s
50 m/s
70 m/s
40 m/s

Explanation:

Step1: Recall velocity - vector formula

The initial speed $v_0$ of a projectile with initial horizontal component of velocity $v_{0x}$ and initial vertical component of velocity $v_{0y}$ is given by the Pythagorean theorem $v_0=\sqrt{v_{0x}^2 + v_{0y}^2}$.

Step2: Substitute given values

Given $v_{0x} = 30\ m/s$ and $v_{0y}=40\ m/s$. Then $v_0=\sqrt{30^{2}+40^{2}}=\sqrt{900 + 1600}=\sqrt{2500}$.

Step3: Calculate the result

$\sqrt{2500}=50\ m/s$.

Answer:

$50\ m/s$