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.
The tides there range from 3.5m (11ft) to 16m (53ft) and cause erosion, creating massive cliffs. This erosion also releases nutrients into the water that help support marine life. Currents associated with the tides are called flood currents (incoming tide) and ebb currents (outgoing tide).Having reliable knowledge about the tides is important for navigating ships safely, and for engineering projects such as tidal and wave energy, as well as for planning trips to the seashore.idal movements are tracked using networks of shore-based water level gauges, and many countries provide real-time information with tidal listings and tidal charts. Tides can be tracked for specific locations in order to predict the height of a tide and when low and high tide will occur in the future.