Next question, 2018's question, it says a block of mass M is placed on a smooth inclined wedge, ABC of Intellition Theta as shown in the figure. The wedge is given an acceleration A towards the right, the relation between A and Theta for the block to remain stationary on the wedge will be. Now, the question of pseudophores is simple, but in this we will not be able to understand the concept of this. This is the example of ABC, ABC is called. Here you have placed a small block, the friction of the surface is zero, and now we have placed this block in this direction. Let's see, these are the parts of the block. Now, we have given this block an acceleration. We have to tell you that this is the angle of Theta and this is the acceleration. Such that this block is the stationary, with respect to the inclined plane, not with respect to ground. This is the stationary, with respect to wedge is our condition. Now, a big simple question, if we make a BD, small M, then it looks like a small M on the bottom of the MG force. And on this, because the acceleration is on the right side, it is on the right side of the MG force. Now, we are looking at this in non-inertial frame, in this respect. So, in this non-inertial frame, behind you, there is an acceleration on this block, behind you. There is no acceleration on this small block, but when we change the frame, then there is acceleration on this. We want this block to be stationary with respect to ground. So, if we write this on the force, if you evaluate it in this direction, then this angle will be Theta, and this is your normal direction, so this angle will be Theta. We will say that if this block is stationary with respect to ground, then this block will be along the inclined plane, this will be the same as the MG-Cost-MG-Sine Theta. And this force, which is there, if this acceleration is there, then we can say that this is the MG-Cost-MG-Cost-MG-Sine Theta. Now, because this stationary is in this frame, then these two components should be equal. So, we can say that MG-Cost-Theta will be equal to MG-Sine Theta, M will get cancelled. And if we take this as the Cost-Theta, then this will be A by G will be equal to 10theta. So, this is our necessary condition for this block to be stationary with respect to inclined plane. So, based on this sum, we can say that option number D is equal to G-Tantheta would be the right answer.