Physics-
General
Easy
Question
Each of the two block shown in the figure has mass m. The pulley is smooth and the coefficient of friction for all surfaces in contact is m. A constant horizontal force P applied in two cases shown in such a way that block A start just sliding then the value of minimum force P in case-I and case-II is :
- 2m mg, 3m mg
- 3m mg, 2m mg
- 4m mg, 3m mg
- 3m mg, 3m mg
The correct answer is: 4m mg, 3m mg
Case-I
P - T -3 mg = ma
putingvalueofTfrom(1)
P - ma - mg ñ 3mg = ma P - 4 mg
a =-2g (2)
Case-II
According to Q.
accelaration is same in both cases
Hence equating the equation (2) & (3)
P =2mg
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