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EfficientEagle2708

I need help with these physics questions this is from a past exam to help me prepare for my exam

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PoutineOrange5768

Hi EfficientEagle2708! 😎

For the first one (12), to understand the direction of the FF, imagine the problem without it. If there was no friction between the two blocks, the upper one would simply stay put while the one on the bottom would slide right. So, to make sure the blocks stay on the same level, we need a force to push the upper one to the right. That force is the friction, therefore why the answer is to the right.

For the second one (2) ⛷️, when you are trying to find the friction, you already put a negative sign before to indicate that it is going to the left. Up until that point, it is perfect. We encounter a problem on the order and signs of your variables.

The - that preceeds the friction indicates that it is going to the left, opposite of the tension. So,

• 0,1 (coefficient), COS of the tension (we want the value in the horizontal axis.

The catch here is the the gravity doesn't add up in the friction because it is already going to the left, you will need to add another - before g because the friction of the gravity is going to the right (opposite of g).

With those corrections, you should be able to find the answer.

I hope this helped! If you have any other questions, feel free to ask!😊