block A has a mass of 10kg and block B has a mass of 25kg. Assume the coefficient of friction between the blocks is four times the coefficient of friction between the block and the plane. Determine the normal force between block B and the plane

To determine the normal force between block B and the plane, we first need to analyze the forces acting on block B. We will consider two forces acting on block B - 1) gravitational force acting downward (mg) and 2) normal force acting upward from the plane (let's call it N).

Since block B is in static equilibrium (i.e., not moving), the net force acting on it is zero. Therefore, the normal force (N) acting on block B is equal to the gravitational force acting on it:

1) N = mB * g (where mB is the mass of Block B and g is the acceleration due to gravity)

2) N = 25kg * 9.8m/s^2

3) N = 245 N (Newtons)

So, the normal force between block B and the plane is 245 N.