Answer:
Change in mechanical energy, [tex]\Delta E=283.2\ J[/tex]
Explanation:
It is given that,
Mass of the projectile, m = 12 kg
Speed of the projectile, v = 20 m/s
Maximum height, h = 18 m
Initially, the projectile have only kinetic energy. it is given by :
[tex]K=\dfrac{1}{2}mv^2[/tex]
[tex]K=\dfrac{1}{2}\times 12\ kg\times (20\ m/s)^2[/tex]
K = 2400 J
Finally, it have only potential energy. it is given by :
P = mgh
[tex]P=12\ kg\times 9.8\ m/s^2\times 18\ m[/tex]
P =2116.8 J
The change in mechanical energy is given by :
[tex]\Delta E=K-P[/tex]
[tex]\Delta E=2400-2116.8[/tex]
[tex]\Delta E=283.2\ J[/tex]
So, the change in mechanical energy is 283.2 J. Hence, this is the required solution.
