A Box (M = 20 Kg) Is Sitting on a Horizontal

question 43

Multiple Choice

A box (m = 20 kg) is sitting on a horizontal surface. It is connected to a massless hook by a light string passing over a massless pulley wheel. The coefficients of friction between the box and the surface are 0.50 (static) and 0.30 (kinetic) . On top of m is a second box M of mass 20 kg. The coefficients of friction between the boxes m and M are 0.80 (static) and 0.60 (kinetic) . How much weight needs to be added to the hook until the box just begins to move.

• A) 10 kg
• B) 98 kg
• C) 20 kg
• D) 16 kg
• E) 200 kg

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Definitions:

Singlet

A term used in spectroscopy to describe a peak or signal that consists of a single line, often related to the absence of splitting in NMR or other spectra.

Ppm

Stands for parts per million, a unit of concentration often used to measure the presence of a substance in a mixture, especially in atmospheric or water pollutants.

NMR Spectrum

A representation of the nuclear magnetic resonance of a substance, providing detailed information about the structure, dynamics, reaction state, and chemical environment of molecules.

Compound

A substance formed from two or more elements chemically bonded together in a fixed ratio, exhibiting properties different from those of the individual elements.