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A bullet of 10 g strike a sand bag at a speed of 1000 m/s and gets embedded after travelling 5 cm.calculate the resistive force exerted by sand on the bullet. |
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Answer» Explanation: MASS of bullet should be =10gm=0.01kg initial velocity (U)of bullet=1000m/s final velocity (V)=0m/s(because it has STOPPED after striking sand) displacement of bullet=5cm=0.05m a)using 2as=V ²-U² 2(a)(0.05)=0²-1000² 2a(5/100)=-1000000 2a(1/20)=-1000000 a(1/10)=-1000000 a=-10000000=-10power7 acceleration of bullet is -10power7or -10000000 by using F=ma F=0.01(10000000) F=1/100(10000000) F=-100000N there fore resistive force of bullet =-100000N b)by using a=v-u/t -10000000=0-1000/t -10000000=-1000/t -10000=t or t=-10⁴seconds |
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