A 0.005kg bullet is fired at 400m/s east at a 12kg block at rest. If the bullet bounces off the block and travels at 150m/s west, what is the velocity of the block?

conservation of mass

mass before something happens = mass afterwards

electric field is a function of 1/r^2

yes, the force per unit charge for a point charge is inverse square law.

the design of a ski jumping suit involves a trade-off between giving the skiers lift to get higher jumps and ensuring the skier does not face a lot of drag before the jump itself. an expansive suit may to lift the skier higher, but at the same time, it will also increase the air resistance. higher air resistance as the skier goes down the slope limits the speed of the jump. a big suit also increases the risk of losing balance or control, especially if there's a strong gust of wind. while technologically enhanced suits a lot, clothing is not the only factor in a ski jumper’s success. gathering speed while skiing down the slope, ensuring good speed on the ramp, and maintaining good body posture and form in the air all contribute to a ski jumper's success.