3 Answers. In general relativity, gravity affects anything with energy. While light doesn’t have rest-mass, it still has energy — and is thus affected by gravity. If you think of gravity as a distortion in space-time (a la general relativity), it doesn’t matter what the secondary object is.

Gravitational attraction provides the centripetal force needed to keep planets in orbit around the Sun and all types of satellite in orbit around the Earth. The Earth’s gravity keeps the Moon orbiting us. It keeps changing the direction of the Moon’s velocity.

Heart of the Matter: The Cardiovascular System The radiation and low gravity of space also has an impact on the body’s vascular system, causing circulatory problems for astronauts when they return to Earth and an increased risk of heart attack later in life.

According to Albert Einstein’s theory of general relativity, black holes are uninhabitable chasms of spacetime that end in a “singularity,” or a mass of infinite density. According to the startling new results, black holes do not culminate in a singularity.

Electrostatic forces are non-contact forces; they pull or push on objects without touching them. Rubbing some materials together can result in something called ‘charge’ being moved from one surface to the other. Charged objects pull on other uncharged objects and may either push or pull on other charged objects.

Magnetic Sand. Black sand on the beaches of La Ventanilla, Mexico, is magnetized. The iron oxide in the sand is attracted to the strong magnetic field produced by the magnet the man is holding. Magnetism is the force exerted by magnets when they attract or repel each other.

Sand is a non-magnetic solid which is insoluble in water.

Magnets are objects, which can attract, or pull, on some metals, like iron and steel. If you rub a piece of steel with a strong magnet, the piece of steel will because a magnet too. It has become magnetized. Other metals, like copper or gold, are not attracted to magnets.

Black sand is sand that is black in color. One type of black sand is a heavy, glossy, partly magnetic mixture of usually fine sands containing minerals such as magnetite, found as part of a placer deposit.

Most types of black sand are formed near a volcano and/or as a result of a volcanic eruption. Others are formed where there are heavy minerals. Each often contain a magnetic mineral called magnetite. Magnetite is a type of iron oxide that is naturally occurring, and it is what makes black sand magnetic.

Black sands (mostly iron) can be and usually is an indicator of gold, but not always. Rule of thumb is you will generally find black sand with gold, but not always gold with black sand.

Iceland

During a volcanic eruption, enough lava can interact this way with the ocean that a new black sand beach can form literally overnight. It is illegal in Hawaii to take lava rocks and sand from the beautiful beaches on any of the islands.

In Ibusuki, a beachside city on Kyushu Island in Japan’s subtropical south, it’s all about the sand. The black sand is actually warm to the touch and soothing to the skin of anyone who travels here to engage in a ritual the Japanese call suna-mushi (sand bathing).

This black sand is mainly composed of ilmenite, magnetite, garnet, zircon and rutile. Also present, in minor or trace amounts, are quartz, sphene, pyroxenes, sillimanite, feldspars, biotite, haematite, tourmaline, chromite, niobian-rutile and pyrrhotite.