00:01
We know that the gravitational attraction between two masses m1 and m2, which are at a distance r, is equal to f equal to g, m1, m2 upon r square.
00:21
It means the force is directly proportional to m1, m2.
00:26
Now here they are asking about the minimum force.
00:30
So for minimum force, the means product m1 m2 should be minimum.
00:40
Secondly, force is directly proportional to 1 upon r square.
00:45
So it means for minimum force, the r should be maximum because force is inversely proportional to r square.
00:59
Now, with this information, we assume that the amount.
01:06
Mass of a concrete block is let us assume it is mc and mass of a marble is equal to m now in case one they are saying two concrete block at six centimeter apart we assume that both concrete blocks are identical to each other and both marble blocks are also identical to each other so in part a the force acting between two concrete blocks six centimeter apart we call it force f1 is equal to g mass of concrete block multiplied by mass of concrete block divided by six centimeter right now in part two they are asking about the force acting between two marbles which are 12 centimeter apart so we call it f2 let this force be f two two marbles it means m m and 12 centimeter apart means 12 into 10 to minus 2 we come to force 3 we call it f3 f3 f3 is the force is a force acting between a concrete block and a marble block 6 cm apart so force f3 will be g concrete block mc marble block m m upon 6 centimeter apart 6 into 10 to minus 2 can in part 4 they are asking about a concrete block and a marble block 12 centimeter apart we call it force f1 so concrete block mc marble block mm divided by 12 cm apart.
03:27
Now for the force, we need to find out which will have the minimum value out of f1, f2, f1, f2, f3 and f4.
03:40
Now as we have seen earlier, that for the force to be minimum, for the force to be minimum, the m1 into m2 should be minimum...