Science Quiz Of Forces (Push And Pull)

Explanation
A force is a push or pull that can cause an object to move, change its speed, or change its direction. In this case, the correct answer is "Push" because it describes a type of force where an object is being pushed in a certain direction. A push can be exerted by a person, a machine, or any other object. On the other hand, a pulley is not a force itself, but a simple machine that can be used to redirect or amplify forces.

Explanation
The given correct answer is "Push, Pull". This answer suggests that the two main forces mentioned in the question are push and pull. Push refers to the act of applying force in a direction away from oneself, while pull refers to the act of applying force in a direction towards oneself. The examples given, such as the lemon squeezer and tin opener, can be associated with either pushing or pulling actions.

Explanation
The two main forces of water are sink and float. When an object is denser than water, it will sink because the force of gravity is greater than the buoyant force exerted by the water. On the other hand, when an object is less dense than water, it will float because the buoyant force is greater than the force of gravity. Therefore, sink and float are the correct forces associated with water.

Explanation
Not all heavy things sink. Whether an object sinks or floats depends on its density. If the object is denser than the fluid it is placed in, it will sink. However, if the object is less dense than the fluid, it will float. Therefore, the statement that all heavy things sink is false.

Explanation
Small objects do not always float. The ability of an object to float or sink depends on its density and the density of the liquid it is placed in. If the density of the object is greater than the density of the liquid, it will sink. Therefore, it is incorrect to say that all small objects float.

Explanation
To open a book, you need to apply a pulling force. This is because the pages of the book are held together by friction and when you pull on one side, it overcomes the friction and causes the book to open. Pushing on the book would not be effective in opening it as it would only compress the pages together, making it more difficult to open. Therefore, pulling is the correct force to apply in order to open a book.

Explanation
A cycle moves slow compared to a plane and a car. While planes and cars are designed for speed and can travel at high velocities, cycles are typically slower due to their design and the physical effort required to pedal them. Cycles have a limited power source (human energy) and lack the mechanical advantages of engines or aerodynamics, resulting in slower speeds. Therefore, a cycle is the correct answer as it moves slower than a plane or a car.

Explanation
The simple machines in the given list are the pulley, tin cutter, bottle opener, and lemon squeezer. These are considered simple machines because they have a basic design and perform a single task with mechanical advantage. A pulley is a wheel with a grooved rim used to change the direction or magnitude of a force. A tin cutter is a tool used to cut metal sheets or cans. A bottle opener is a device used to remove bottle caps. A lemon squeezer is a tool used to extract juice from lemons or other citrus fruits.

Explanation
Blowing is considered a force of nature because it is a natural phenomenon caused by the movement of air. Wind is created by the pressure differences in the atmosphere, and it can exert a force on objects, causing them to move or be influenced by its power. Blowing is a common occurrence in nature and can have various effects on the environment, such as shaping landscapes, dispersing seeds, and causing weather changes.