The First of Two Identical Boxes of Mass M Is

question 67

Multiple Choice

The first of two identical boxes of mass m is sitting on level ground. The second box is sitting on a ramp that makes a 20° angle with the ground. The normal force of the level ground on the first box is N_L; the normal force of the ramp on the second box is N_R. Which statement is correct?

• A) N_R = N_L = mg.
• B) N_L = mg; N_R = mg sin 20°.
• C) N_L = mg; N_R = mg cos 20°.
• D) N_L = mg; N_R = −mg cos 20°.
• E) N_R = −N_L = −mg.

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Definitions:

Andesite

An intermediate-composition igneous rock that is the fine-grained equivalent of diorite; typically gray or greenish-gray, commonly with phenocrysts of cream-colored feldspar or dark amphibole.

Magma Chamber

A reservoir of molten rock beneath the surface of the Earth or a volcano.

Felsic Igneous Rock

Igneous rocks that are rich in silica and light in color, such as granite, characterized by minerals like quartz and feldspar.

Igneous Rock

A type of rock formed through the cooling and solidification of magma or lava, with examples including granite and basalt.