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i sometimes don't know why momentum is conserved is these cases(for both linear and angular), i know that for momentum to conserve , external net force(linear) or external net torque should be zero
can someone please help me with the following two condition??
Case1
A bomb is projected to the mid air, and then exploded in the mid air and two fragments are formed
we have
(Mass of the bomb)( velocity before explosion) = (Mass of fragment 1 )( V of F1) + (M of fragment 2 ) ( V of F2)
Why?? i think there is a external force acting on the bomb and it is Mg ? after explosion there are also m1g and m2g acting on the fragments respectively? why conserved? the net force is not zero
Case2
In fact it is a question that was asked in this forum before, but i dun understand the concept
Two balls of mass 2.26 kg are attached to the ends of a thin rod of negligible mass and length 72 cm. The rod is free to rotate without friction about a horizontal axis through its center. A putty wad of mass 145 g drops onto one of the balls, with a speed 2.7 m/s, and sticks to it. What is the angular speed of the system just after the putty wad hits?
Why the angular momentum conserved just b4 and after collision ? there is a external non zero net force acting on system that is the weight of the putty wad?
i know how to do these question but i dun know the concept, can anyone help
can someone please help me with the following two condition??
Case1
A bomb is projected to the mid air, and then exploded in the mid air and two fragments are formed
we have
(Mass of the bomb)( velocity before explosion) = (Mass of fragment 1 )( V of F1) + (M of fragment 2 ) ( V of F2)
Why?? i think there is a external force acting on the bomb and it is Mg ? after explosion there are also m1g and m2g acting on the fragments respectively? why conserved? the net force is not zero
Case2
In fact it is a question that was asked in this forum before, but i dun understand the concept
Two balls of mass 2.26 kg are attached to the ends of a thin rod of negligible mass and length 72 cm. The rod is free to rotate without friction about a horizontal axis through its center. A putty wad of mass 145 g drops onto one of the balls, with a speed 2.7 m/s, and sticks to it. What is the angular speed of the system just after the putty wad hits?
Why the angular momentum conserved just b4 and after collision ? there is a external non zero net force acting on system that is the weight of the putty wad?
i know how to do these question but i dun know the concept, can anyone help