I am trying to determine the velocity of a ball fired horizontally from ballistic pendulum. The data is as follows:(adsbygoogle = window.adsbygoogle || []).push({});

ball mass: 62.2 g

spring mass: 14.7 g

rod mass: 89.3 g

length of spring: 126.1 mm

initial spring length: 5 cm

compressed spring length: 1 cm

k: 2.05 N/m calculated from previous experiment

Using the Work-Kinetic Energy Theorem

Kbo + Kro + Kso = Kb + Kr + Ks

.5mv^2oball + .5mv^2orod + .5kx^2 = .5mv^2ball + .5mv^2rod - .5kx^2

I took all the terms to 0 and got v_oball = (kx^2 /m_ball)^.5.

this doesn't seem correct, shouldn't the mass and lengths of the spring and rod be used?

2nd part is to determine the range it should travel from a height of 101.05 cm above ground fired horizontally.

I used the R = v^2 /g sin2t but since angle t= 0 I am getting 0 for the range.

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# Homework Help: Velocity of a projectile fired horizontally from a spring launcher ballistic pendulum

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