Question

Solve it....................!!!!​

Answer 1

Answer:

Explanation:

M=0.05kg,u=100m/S,v=0,s=0.02m

1) Now initial momentum mi=m*u

Mi=0.05*100=5kgm/s

2) Final momentum=m*v=0.05*0=0

3)v²=u²-2as

0=(100)²-2a0.02

A=retardation=10000/0.04=250000m/s²

4)f=m*a=0.05*250000

F=12.5kN

Answer 2

★ Given:

Mass of bullet = 50 g

Initial velocity (u) = 100 m/s

distance (s) = 2cm

Final velocity (it comes to rest) = 0

★ To find:

i) initial momentum of bullet

ii) final momentum of bullet

iii) retardation caused by wooden block

★ Solution :

We know that,

Momentum = Mass × Acceleration

$i) \:p_{initial} = m \times u \\ \\ \\ = \frac{50}{\cancel{1000}} \times \cancel{100} \\ \\ \\ = \frac{\cancel{50}}{\cancel{10}} \\ \\ \\ p_{initial} = 5 \: kgm/s$

$ii) \: p_{final} = m \times v \\ \\ \\ = \frac{50}{1000} \times 0 \\ \\ \\ p_{final} = 0$

$iii) \: We\: know\: that \\ \\ \\ v^2= u^2+2as \\ \\ \\ by \: putting\: the\: value \\ \\ \\ (0)^2 = (100)^2+ 2a \times \frac{2}{100} \\ \\ \\ 0 = 10000 + a \times \frac{1}{25} \\ \\ \\ 10000 = \frac{-a}{25} \\ \\ \\ by \: cross \: multiplication \\ \\ \\ -a = 250000 \\ \\ \\ a = -250000 \\ \\ \\ a = -2.5 \times 10^5 \: m/s^2$

*Note - minus sign represents retardation .

$iv)\: We \: know \: that\\ \\ \\ \bold{F = ma } \\ \\ \\ by \: putting \: values \\ \\ \\ F = \frac{\cancel{50}}{\cancel{1000}} \times 2.5 \times 10^5 \\ \\ \\ = \frac{1}{20} \times 2.5 \times 10^5 \\ \\ \\ = \frac{1.25 \times 10^5}{\cancel{10}} \\ \\ \\ = 1.25 \times 10^4 \\ \\ \\ \bold{\therefore \: F = 12500 \: N}$