Unit 3 Summary

Newton’s 3rd Law and  Action/Reaction Pairs:

Newton's 3rd law states that: "Every action has an equal and opposite reaction". This means that if someone pushes you are pushing back at him with the same force. If you pull something it will pull you back with the same force. If the earth is pulling you, you are pulling the earth with the same force.

Tug of War / Horse and Cart:

If their was a horse pulling the cart along the street the pull on the rope isn't whats making the cart move with the force, as every action has an equal and opposite reaction, so the net force on the rope is 0 (zero). The horse is able to move the cart because the force he is pushing the ground at is greater than the force the cart is pushing the ground at. So the ground will push the horse forward with an equal and opposite force, the same with the cart. So the equal and opposite force of the horse is greater than the equal and opposite force of the cart, so this is house the horse is able to move the cart.

Forces in Perpendicular directions:

If there was a plain flying to the north direction at 10m/s and the air was blowing at 10m/s to the east. The plain would then be going to the North-east direction as it is the exact midway of both forces, and it has both horizontal and vertical forces acting on it. The plain will also be moving at a speed of 14.1, this is because the plain and the wind form and 10, 10, 10 root 2, triangle.

Gravity and Tides:

Tides are manly caused by the moon than the sun this is because, the moon is closer to the earth. This can be explained by this formula G*(m1m2)/(d^2) this formula if applied shows that the sun has a greater force on the earth than the moon does. But the tides do not depend on the amount of force affecting the sides but the difference of the certain point of the earth from the center of the earth.