'cause many alpha-particle goes without any deflection........
Ultrasound is sound or vibrations, having an ultrasonic frequency, particularly as used in medical imaging. Ultrasound is more commonly used in medical terminology than in industry. Infrasound is sound waves with frequencies below the lower limit of human audibility.
Newton's third law of motion states that for every action force, there is an equal and opposite reaction force so that means that the wall is pushing you with the same amount of force that you put on it.
Tendons connect muscle to bone. Ligaments connect bone to bone.
If you need more info I can give some more.
Hope this helps