00:01
Well, mass of the bullet is equal to 30 grams.
00:05
Mass of bullet m is equal to 30 grams, and 30 grams is equal to 30 divided by 1 ,000 kilograms, and it's equal to 0 .03 kilograms.
00:23
Kilograms and the initial horizontal velocity of the bullet initial horizontal velocity of the bullet and let's say be not and it's equal to 500 meter per second and also the bullet stops after moving a distance x is equal to 12 centimeter within a solid wall so the bullet moves distance equal to 12 centimeter within a solid wall.
01:02
Now let's solve part a.
01:06
Well, in this case, change in mechanical energy, delta e mechanical is equal to change in kinetic energy, delta k, and delta k is kinetic energy final, minus kinetic energy initial.
01:23
And we have delta e mechanical is equal to 0 minus half mv0 squared so a final kinetic energy of the bullet is zero since it comes to rest and putting the values we have change in mechanical energy is equal to minus 1 divided by to multiply by 0 .03 multiply by 500 square and therefore change in mechanical energy is equal to minus 3 ,750 joules minus 3750 joules is the change in mechanical energy.
02:25
Now let's solve part b, we know that part b, v.
02:37
V -a -square is equal to v -i -square plus 2ax...