Ehy Newton's law of gravitation also called universal law?

Gravity is a natural phenomenon that causes all massive objects to attract each other. The magnitude or force of this interaction depends on the masses and distance of the bodies. This causes objects to fall toward Earth, for example, and keep satellites and celestial bodies in their orbits, such as the Earth's orbit around the Sun. Gravity also causes the tidal phenomenon.

In physics, gravity can be approximated by Isaac Newton's laws of gravity. Although the accuracy of the law is sufficient, for example, when calculating the orbits of spacecraft, gravity is best described by Albert Einstein’s general theory of relativity, in which it is considered the curvature of space-time.

the part of the wave he is travelling on is the crest

answer: 2×10^-2kg

explanation: density= mass per volume

vol=mass/density

converting to s.i units we have;

3÷1000kg = 0.003

1.5÷100m = 0.15

0.003/0.15 = 0.02kg