(1)
Which medium does the sound travel the fastest?
Solid
The substance that sound waves move through is called...
medium
State the layer of earth that forms the centre
Inner core
Why cant sound travel in vacuum?
There are no particles for it to vibrate
What is the reflection of a sound called?
Echo
What is the meaning of vibrate?
To move back and forth quickly
Sound can vary in...
1.
2.
1. Loudness
2. Pitch
What energy is responsible to transfer sound waves?
Sound energy
The sound travelling from a vibrating object to our ears is called...
Sound wave
State 3 ways an echo is useful
1. Boats- to find the depth of water
2. Bats- to find prey
3. Dolphins - to find prey
4. ultrasound - images of unborn baby
1. Crust
2. Mantle
3. Outer core
4. Inner core
Why do tectonic plates move?
due to the movement of liquid magma beneath them
What is the name of the place where tectonic plates meet
Plate boundaries
What is the name of the plate boundaries where there are a lot of volcanic eruptions and earthquakes?
Pacific Ring of Fire
What are the three types of plate boundaries?
1. Plates moving together: Subduction
2. Plates moving apart
3. Plates sliding past
Plates that move apart create....
volcanoes
Plates that slide past each other create...
earthquakes
What are fold mountains?
Formed when tectonic plates move together , and the rock crumple and fold upwards
Give two examples of fold mountains
1. Himalayas
2 Rocky Mountains in North America
3. Ural Mountains - Russia
How does volcano form ?
At the plate boundaries, when magma rises up through the cracks in the Earth crust
What is the formula for the speed of a volume?
Speed = Distance / Time
What are the two conditions needed to hear a sound?
1. a vibration
2. a medium
1. The shapes of the continents fit together
2. The types of rock on different continents match
3. The fossils on different continents match
The size and magnitude of an earthquake is determined through ?
a. Size of the faults at the plate boundaries
b. How far the rock moves
How does earthquake happen?
When there is pressure on the tectonic plates. and there is a build-up of this pressure causing a violent movement.