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Waves

  • A wave transfers energy through matter and space without moving the matter.
  • Two main types of waves: Mechanical Waves and Electromagnetic Waves
    • Mechanical Waves – need a medium to travel through
    • Electromagnetic Waves – can travel through matter or empty space
  • Two types of mechanical waves: Longitudinal (Compressional Waves) move the matter back and forth in the same direction of the wave and transverse waves that move the matter at right angles to the direction of the wave.
  • Light waves travel faster than sound waves
  • Wave speed depends on medium the wave is traveling through.
  • Compression waves travel faster in liquids and solids than in gases.
  • Electromagnetic waves faster in gases and empty space than through liquids and solids.
  • Reflection occurs when waves strike and bounce off an object. Refraction occurs when a wave bends as it changes speeds as it travels from one medium into another. Diffraction occurs when waves bend as they move around an object.
  • Visible light are the wavelengths on the electromagnetic spectrum that can be detected by your eyes. All wavelengths of visible light make white light.
  • Light can be reflected, refracted, transmitted, absorbed by matter. Objects can only be seen if light reflects off the object.

Waves

What unit is used to measure force?

Newtons

The motion of an object changes when forces are (1,0)20.

Unbalanced

What is said about the forces when the net force on the object is zero?

The forces are balanced and the object is not changing direction.

How do you calculate the net force on an object when the forces are pushing and pulling in the same direction?

Add the forces

What force brings all objects to a stop?

Friction

What type of friction is present between a car at rest and the ground it is resting upon?

Static friction

Which of Newton’s laws of motion is also known as the law of inertia?

The first law of motion

According to Newton’s second law of motion, if the force applied to an object is a push from left to right, in which direction will the object accelerate?

To the right

According to Newton’s third law of motion, if the force you apply to the ground while standing still is 450N down, what is the force the ground is applying to you?

450 N up

You and your bumper car together have a mass of 240kg. The momentum of the bumper car that runs into you and stops is 480 kg x m/s. At what velocity will you be traveling after the collision?

Your velocity will be 2 m/s

*These practice questions are only helpful when you work on them offline on a piece of paper and then use the solution steps function to check your answer.

Answer

Waves

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Chemistry: Physical Science