Ultrasound is sound or other vibrations having an ultrasonic frequency, particularly as used in medical imaging. Also, Infrasound is sound waves with frequencies below the lower limit of human audibility.
I believe the answer is A.
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Density is defined as (mass) per unit (volume). So in order to calculate
the density of a glob of some substance, you pretty much have to measure
its mass and its volume.
Density = 2 g/cm ^3 (if that’s the question)
Answer:
Mass of bike = 38 kg.
Explanation:
Kinetic energy is given by the expression, , where m is the mass and v is the velocity.
Here speed of child riding bike = 6 m/s
Mass of child = 30 kg
Total kinetic energy = 1224 J
Let the mass of bike be, m kg
So, total mass of child and bike = (m + 30) kg
Substituting,
So, mass of bike = 38 kg.