Finding Velocity with Volume/KE/Density.?

Question

A uranium projectile fired from a tank in Iraq has a volume of 340.20 cm3 and an intital kinetic energy of
1.98 x 103 kJ. What is the muzzle velocity of the tank's gun (m/s)?
The density of uranium is 18.95 g/cm3.
I am unsure where to begin. I use the formula E(kinetic) = 1/2 m * v^2. Do I set d = m/v to determine the mass and then proceed forth from there?

Answer 1

yes.
First find the mass using the density equation: 18.95=m/340.2, m=6446.8g
Then you can calculate velocity from kinetic energy.
1.98x10^6 j=.5(6.4468kg*v^2)
v^2=613954
v=785m/s
Check numbers in calculator(i was doing by hand)

Note you have to convert the kiljoules to joules to multiply it by meters. Joule=newton*meter

Answer 2

m = 18.96 g/cm³ * 340.30 cm³
...= 6452.1g
...= 6.4521 kg

KE = 1/2 mv²

v = (2KE/m)^1/2
...= (2*1.98E6/6.4521)^1/2
...= 783.42 m/sec