Sand and silt are both examples of granular materials, which are collections of separate particles and distinct particles, such as raw flour in a container or jellybeans in a jar.The most common forms of sand and silt are composed of tiny fragments of quartz.
Rip tides, also known as rip currents, are strong narrow currents that can pull swimmers out to sea. Some rip tides are so strong that they can drag swimmers away from shore before they realise what is happening. Swimmers should keep an eye out for rip tides while swimming in the sea at the beach. Rip tides can be identified by discoloured water, choppy waves and a foamy surface. They can be filled with debris. Swimmers are told to remember the âthree Rsâ if they become caught in a rip tide.
Rips often occur at groins, jetties and piers; stay at least 100 feet away from these structures in the water to avoid these deadly currents and other hazards. Â» About 100 people drown annually in rip currents in the United States. Â» Breaking waves that approach 5 feet can generate powerful rip currents.urrent speeds are quite fast, often reaching 2-3 feet per second and measured to be as high as 6 feet per second along some Australian high-surf beaches. The neck of the rip can vary in width from a few yards to tens of yards.