Test: Turning effect of a force - Year 8 MCQ

There is no correlation between the position in the reactivity series and how well a metal conducts electricity

In a displacement reaction, a more reactive metal can replace a less reactive metal from its compound. For example, if you place a piece of zinc in a copper sulfate solution, zinc will displace copper from the solution, forming zinc sulfate and copper metal. This is because zinc is more reactive than copper.

When metal carbonates react with acids, carbon dioxide gas is produced. This gas can be tested for using limewater (calcium hydroxide solution). Carbon dioxide gas turns limewater milky/cloudy due to the formation of calcium carbonate, which is insoluble in water. This reaction is a classic test for the presence of carbon dioxide gas.

Torque (or moment of force) is the term used to describe the turning effect of a force around a pivot point. It depends on both the magnitude of the force and the distance from the pivot point where the force is applied.

The torque produced by a force depends on its magnitude and the perpendicular distance from the pivot point (lever arm). The direction of the force relative to the pivot point also plays a crucial role in determining the torque.

Torque is calculated as the product of the force and the perpendicular distance (lever arm) from the pivot point to the line of action of the force. Applying a force with a longer lever arm increases the lever arm distance, thus producing a greater torque compared to applying the same force with a shorter lever arm.