A particle of mass m is driven by a machine that delivers a constant power K watts. If the particle starts from rest, the force on the particle at time t is
A.
As the machine delivers a constant power
So F, v =constant = k (watts)
Three blocks A, B, and C of masses 4 kg, 2 kg and 1 kg respectively, are in contact on a 14 N is applied to the 4 kg block, then the contact force between A and B is
2 N
6 N
8 N
18 N
B.
6 N
Given, m_{A} = 4 kg
m_{B} = 2 kg
=> m_{C} =1 kg
So total mass (M) = 4+2+1 = 7 kg
Now, F = Ma
14 = 7a
a=2 m/s^{2}
F-F' = 4a
F' = 14-4x2
F' = 6N
A block A of mass m_{1} rests on a horizontal table. A light string connected to it passes over a frictionless pulley at the edge of the table and from its other end, another block B of mass m_{2} is suspended. The coefficient of kinetic friction between the block and the table is . When the block A is sliding on the table, the tension in the string is
C.
FBD of block A,
T -m_{1}a_{ = }f_{k} ..... (i)
FBD of block B
A stone is dropped from a height h. It hits the ground with a certain momentum p. If the same stone is dropped from a height 100% more than the previous height, the momentum when it hits the ground will change by
68%
41%
200%
100%
B.
41%