Question

Please help with number 6, or any of them

Answer 1

Number 6:

• From the formula of force:

`force = mass * acceleration \\ { \boxed{f = ma}}`

• But we need to get the acceleration, from the first newtons equation of motion

`v = u + at`

• v is the final velocity, but v is zero because the bullet came to rest.

• u is the initial velocity, u = 350 m/s

• a is the acceleration that we need

• t is the time, t = 0.0018 seconds.

» let's now substitute:

`0 = 350 + (a * 0.0018) \\ 0.0018a = - 350 \\a = - 194444.44 \\ { \underline{ \: \: |a| = 194444.44 \: m {s}^( - 2) }}`

[ negative shows retârdation or deceleration or decrease in speed ]

• Therefore, let's find the force:

mass = 6g = (6/1000) kg = 0.006 kg

`force = m * |a| \\ f = 0.006 * 194444.44 \\ { \underline{ \underline{ \: \: force = 1166.67 \: \: { \sf{newtons \: \: }}}}}`